Emerson Transmitter LTM-300 Operating Instructions
Contents
1. Basic Level Transmitter Simplified Block Diagram Facilities are provided to field calibrate the range of the 4 20 mA output using the actual position of the float and pressing a push button on the front panel to set the 4 20 mA point Provision accessed through HART or front panal is made for a FAIL mode to High 20 8 mA Low 3 75 mA or Hold last Value A HART modem enables the transmitter to communicate serially over the 4 20 mA DC signal with a host computer or a handheld terminal 2 Level Temperature An optional temperature sensor is embedded inside the bottom tip of the probe and it can be calibrated to give the temperature of the liquid in the tank on the second or third The sensor is a 1000 ohm platinum RTD type and its resistance is converted to a binary signal by a high resolution A D Converter The temperature range is set to order and stored in non volatile memory before shipment V es Y 4 mA MODEM s PRIMARY LOOP 4 20 mA HART comm F1 re F3 F4 WA 1 gt DIGITAL A D Temp RTD ol aN i D 3 Level Interface A second float may be added below the first one and the second output will be calibrated automatically The second time interval is measured in the same manner as the f2. Inductive Magnetic Detector Flisai The effect of this torsion force is to twist the wire at this point producing a torsion wave traveling towards both ends of the wire The propagation time of this wave is measured precisely and if the wire properties remain stable it is very repeatable at about 5 10 microseconds per inch which is approximately the speed of sound in that medium By measuring the exact number of microseconds it took the torsion wave to reach a designated termination point of the wire the distance to the magnet from this termination point can be easily calculated A high speed micro controller is utilized in the design to process and calculate the elapsed time measurement Accurate crystals are used for the time base to resolve sub microsecond timing increments The binary number equivalent to the microseconds of the echo travel time is written to an output D A Converter and subsequently converted to a 4 20 mA signal proportional to the item measured The larger the number of microseconds there are the greater the distance of the float from the head of the transmitter Calibration routines are included in the software to scale the 4 and 20 mA points for any distance desired Even reverse calibration is a simple task using the software routines Reverse calibration is desirable if ullage instead of full level is required or when the probe is installed with bottom mount head See Section on Calibration for further detail
3. Innovators not Imitators LTM 300 Series Magnetostrictive Level Transmitter Instruction amp Operation Manual J an 2009 3902 Magnolia Road Pearland Texas 7 584 PH 281 488 0788 FAX 281 488 7080 EMAIL magtech isemagtech com www isemagtech com LTM 300 Magnetostrictive Level Transmitter Instruction and Maintenance Manual Table of Contents Section 1 Transmitter Overview Page 1 0 General Description 1 1 1 Level Transmitter 1 1 2 Gage Mounted Transmitter 1 1 3 Standalone Transmitter 1 Section 2 Instrument Description Page 2 0 Transmitter Detailed Description 2 2 1 TheoryofOperation 2 ZA Primary Level ii oan AUIWA aa ai 2 2 1 2 Level Temperature Transmitter 3 2 1 3 Level Interface Temperature Transmitter 3 Section 3 Installation and Wiring Page 3 0 Strap On Transmitter Installation 3 3 1 Standalone Transmitter Installation 3 3 2 Recommended Wiring Single Loop 4 Section 4 Specifications Page 4 0 Transmitter Electrical Specifications 4 4 1 Transmitter Sensor Tube 4 Section 5 Calibration Page 5 0 S
4. again The HART Communicator will now command the transmitter to set the current output to 20 000mA The user must press OK when ready to have the current output set to 20 000mA When the device has set the current output to 20 000mA the user is to enter the reference meter reading For example if the meter actually reads 19 975mA that value is input with the keypad The user must press ENTER when ready to proceed The transmitter based on the data from the reference meter will calculate a new value for the DAC gain calibration constant and change the output current based on the new constant If the current read by the reference meter is now 20 000mA the user must press ENTER If not exact the user must select No and press ENTER to try again The Current Output calibration is now complete The HART Communicator will now return the current output of the transmitter to normal operation The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Calibration screen The HART Communicator is now at the starting screen for the Scaled D A trim The HART Communicator is now at the starting screen for the Zero Level Trim Zero Level Trim Starting at the Calibration screen select the Zero Level Trim procedure This procedure trims the Level digital value measurement at the position that the user desires to be t
5. Interface to the position that is to provide the 20mA loop current output When that has been done the user must press OK to continue with the procedure The HART Communicator then requests a measurement reading from the transmitter indicating the digital value at this range position The user then has the option of setting this value as the upper range value getting an update of the digital reading from the transmitter or leaving the 20mA range point as it was If the user accepts the measurement value as the 20mA loop current point the HART Communicator issues the command changing the URV and when the transmitter replies returns to the Set screen When the user desires to leave the Apply values procedure he must select the Exit menu entry The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Rerange screen In the Overview section it was shown that if the user selects the Detailed setup menu from the Device setup screen the following screen presents the following selection of menus to the user If the user selects Sensors from the Detailed setup screen he may edit the Unit code for Level Interface or edit the units code for Temperature The third option is a menu Sensor Trim that gives the user additional selections If the user selects Sensor Trim from the Sensors menu calibration procedure opt
6. selecting Operation Status or Cal Status only viewing the off normal status by selecting View status and if a maintenance status bit is set to reset that bit as shown below If the user selects Operation Status from the Diagnostics screen he is able to view all of the status bits indicating the health of the transmitter operation If the entry is labeled OFF that means that the entry is in normal operating conditions If the entry is labeled ON that means that the transmitter diagnostics has detected an abnormal condition and the user needs to take corrective action The user is able to scroll down through the list to check each Status bit In the example given the transmitter diagnostics has detected a problem with the Level measurement that may require user intervention If the transmitter is not configured for Interface or Temperature those status bits will always be listed as OFF To return to the Diagnostics screen the user must press EXIT If the user selects Cal Status from the Diagnostics screen he is able to view all of the status bits related to the calibration of the transmitter User calibration is required for Level Temperature and DAC output If the transmitter diagnostics detects a calibration constant out of range this will be reported by one of the status bits being set ON The user is able to scroll down through the list to check each status bit In the example given the dia
7. transmitter properly 3 Make sure the 4mA markings on the sensor tube are re aligned at the centers of the process connections 7 1 Insulation Warning Label Supplied When Insulating Gages MagTech Level Transmitters have a maximum operating temperature of 300 F When insulating a Mag Gage and transmitter assembly in HOT service keep the transmitter OUTSIDE the insulating material Special blankets for this type of insulation are available from MagTech For further information consult the factory 1 800 221 3653 SECTION 8 Warranty and HART Protocol 8 0 Warranty All MagTech products are warranted against defects in materials and workmanship of one year from date of shipment The level gage chamber and process connections are guaranteed for the life of the tank or vessel to which it is attached Floats are guaranteed for two years MagTech will repair or replace at its discretion those products that fail to perform as specified with the following exceptions 1 Products repaired or modified by persons that are not authorized by MagTech 2 Products subjected to misuse negligence or accidents 3 Products that are connected installed or otherwise used in such a way not in strict accordance with manufacturer s instructions This warranty is in lieu of any other warranty expressed or implied by any party other than MagTech Repairs and or replacements shall be at the sole discretion of MagTech based on the terms and
8. wire and require a minimum of 15 Volts at 20 mA 1 Using a HART compatible loop calibrator connect the terminal on the LTM to positive lead of calibrator and the terminal on the LTM to negative lead of calibrator 2 With float in the gage at 4mA the output of the LTM should be 4mA Connect the HART Communicator to the transmitter Upon power up the HART Communicator should read the LRV lower range value or 0 inches at 4mA 3 With float in the gage at 20mA the output of the LTM should be 20mA HART should also display URV upper range value or span length in inches at 20mA 4 To insure complete functionality of gage and transmitter fill the gage chamber with liquid and drain slowly to observe transmitter and gage are tracking properly 5 Ifno float is present or magnetic field is lost HART Communicator will display LEVEL SIGNAL LOST 6 For calibration using HART or to change range consult HART section of this manual Note In service over 400 Deg F 204C Gages and Transmitters should be properly insulated with transmitter OUTSIDE the blanket Note During the installation or calibration of the LTM 300 level transmitter the technician should be very careful not to move the magnet perpendicular to the sensor tube as this could leave magnetic indentation in the sensor wire The LTM 300 level transmitter has an inductor located inside the bulkhead of the sensor tube During operation of the t
9. conditions of this warranty Defective products shall be returned to the factory prepaid by the buyer after obtaining a Return Authorization Number from MagTech All warranty repairs or replacements will be preformed at the factory in Houston Surface return freight will be paid by MagTech Factory warranties do not include field service Field service warranty repairs will be at the buyer s expense Consult MagTech for field service rates Any modifications to terms and conditions of this warranty will not be binding unless made in writing and signed by an authorized agent or official of MagTech NOTE ALL MAGTECH GAGES SHOULD BE UNPACKED AND THOROUGHLY INSPECTED UPON RECEIPT GAGES ARE SHIPPED FOB FACTORY AND ARE FULLY PROTECTED AGAINST DAMAGE OR LOSS DURING SHIPMENT ANY CLAIMS FOR PARTS DAMAGED DURING SHIPMENT SHOULD BE SUBMITTED WITHIN 15 DAYS OF RECEIPT OF GOODS BY CUSTOMER If the user selects Basic setup from the Device setup screen the next screen has a mixture of further menu selections and detailed information This screen displays the name of the variable that is controlling the output current PV 8 1 HART Protocol Option Information HART Communicator Overview This section presents the major screen selections available to the user The HART Communicator screens are shown on the left and a description of the screen and user information is given on the the tag and the Alarm type In right addition this screen prese
10. only way to end this series of screens is to select EXIT since the list is a continuous loop through the parameters Diagnostics and Service The user accesses this screen by selecting Diag Service from the Device setup screen There are to further menu selections Diagnostics and Calibration and two procedures Loop test and Restore Defaults that the user may select from this screen When the user selects the top menu entry on the root menu Device setup by using the right arrow the next screen displays five menu selections available to the user Each of these menu selections will provide detailed information about a specific portion of the transmitter as detailed in the following sections If the user selects the Process variables menu from the Device setup screen the next screen displays the current values for all of the dynamic variables If the transmitter is not configured for Interface the entry Interf is not displayed If the transmitter is not configured for temperature the entry Temper is not displayed If the user selects Diag Service menu from the Device setup screen the next screen displays further menu selections to the user These selections will be presented in more detail in the section titled Diagnostics and Service following this Overview If the user selects Diagnostics from the Diag Service screen he is given the choice of viewing the complete diagnostics status by
11. temperature output 4 0 Transmitter Electrical Specifications Repeatability 005 of full scale or 010 Configurations two and three have independent calibration as well whichever is greater as independent outputs These configurations have the capability for calibration and measurement using a HART protocol communications system The HART specifications and conditions will be discussed in detail under the HART COMMUNICATION section of the manual The temperature range is factory set from 50 F to 300 F Non Linearity 01 of full scale or 030 whichever is greater Level Sensor Accuracy 01 of full scale or 020 whichever is greater ae Pushbutton Calibration Analog Output Resolution 025 of full scale 1 4 20 mA primary level Step 1 Move jumper to the write enable position see below Step 2 Move your float or magnet to the 4mA 0 point on the probe Output One 4 20 mA output Step 3 Press the ENTER button on the display until Trm Snsr is Level Option Two Digital displayed Press the UP arrow to display Yes and press ENTER Outputs Temperature and or Step 4 The display will read Trim Zero Press ENTER Interface via HART only Step 5 Move the float or magnet to the 20mA 100 point on the probe Calibration Zero and span field adjustable Step 6 The display will read Trim Span with a value above Using the with push buttons or HART arrow buttons input the correct distance from
12. that the polarity is reversed TERMINAL BOARD 6 4 Start Up for Gage Mounted LTM Transmitters Gage and Transmitter Installation 1 Visually inspect Mag Gage and transmitter installation to insure transmitter is positioned with the 4 mA and 20 mA labels directly adjacent to the process connections Make sure transmitter is securely clamped and parallel to gage chamber 2 Remove bottom flange and install float Each float is clearly tagged with serial number of the Mag Gage and process parameters Top of float is clearly marked TOP to insure float is in right side up 3 Inspect bottom flange for proper gasket and spring This spring protects float and keeps it from dropping below the bottom process connection To determine proper spring length measure A dimension of gage This is the length from the center of the bottom process connection to face of the bottom drain flange Length of spring should be A DIMENSION Minus Float Length 2 inches EXAMPLE A Dimension is 14 Float length is 127 2 4 Spring Length 14 12 2 4 spring 4 Float is properly installed if the bottom 2 3 flippers on gage indicator have flipped NOTE There is a top spring in the Mag Gage to protect float and prevent it from passing the top process connection DO NOT REMOVE EITHER SPRING Transmitter Check out and Calibration NOTE The LTM Series Transmitters are 24VDC Loop powered 2
13. the value to the transmitter If the user selects URV from the Keypad rerange screen the present URV is displayed above the edit box 60 00 in as shown to the left In this example the user desires to change the URV to 55 0 in and must press ENTER after changing the edit box to continue with the reranging of the transmitter 16 On returning to the Keypad rerange screen the values shown for LRV and URV are the changes that the user has made The user should check the difference between the URV and LRV and compare this value with the Min span listed on the menu If the difference is smaller than the minimum span the transmitter will not accept the new range values Note that the label above F2 is now SEND The user must press the SEND key for the HART Communicator to send the new range values to the transmitter The HART Communicator will display this screen reminding the user that the loop should be removed from automatic control before proceeding When this has been done the user must press OK to continue The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Keypad rerange screen The keypad rerange screen now shows the new LRV URV and Unit selected by the user Reranging the Transmitter Setting the Measurement Value for 4mA and 20mA by Apply Values If the user desires to set the 4mA and 20mA meas
14. trim point The second trim point can be any other level point but it is recommended that this point be as far away from the zero point as possible When the float is at this position the transmitter will always report the digital value entered in the user chosen units The user must press OK when the float is at that position The transmitter will take several seconds to insure that the level signal has stabilized Once the measurement is stable the procedure will continue without user intervention The HART communicator will then send the command to the transmitter to calculate the new Level gain calibration constant The HART Communicator will now request the user to enter the value at the high trim point The HART Communicator will display the last upper trim point for example 60 in and the user will enter the new upper trim point for example 59 0 in The HART Communicator will now send this value to the transmitter When the transmitter has completed its calculation of the new Level gain calibration constant it will reply to the HART Communicator Then the HART Communicator will inform the user that the level upper trim point has been trimmed Then the HART Communicator will inform the user that the upper level trim point has been trimmed The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Calibration screen T
15. user must acknowledge the end of the list by pressing OK to return to the Diagnostics screen Two of the Operation status bits Level Maintenance Needed and Interface Maintenance Needed when set by the transmitter diagnostics will remain set including power cycles until reset by the user After the user has corrected the maintenance problems these status bits should be reset by accessing the Reset Maintenance procedure When the user selects the Reset Maintenance option the HART Communicator displays the warning message that the loop should be removed from automatic control during this procedure The HART Communicator then asks the user to select YES or NO for the procedure to continue As shown here the user selects YES to continue Then the HART Communicator sends the command to reset the maintenance needed status bits The HART Communicator informs the user that the maintenance flags have been reset when the transmitter has replied to the reset command The user must acknowledge this information by pressing OK to continue The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Diagnostics screen The user must use the left arrow to return to the Diag Service screen If the user selects Loop test from the Diag Service screen a procedure will begin that will allow the user to set the loop current to a
16. WING NUMBER PLEASE DO NOT DUPLICATE OR CIRCULATE 3000 3 2 Recommended Wiring Ambient Temp Range 20 C 40 C 4 F 104 F Single Loop Humidity Limits SAMA PMC 31 1 5 2 Vibration Limits SAMA PMC 31 1 5 3 RFI Limits SAMA PMC 31 1 20 to 1000 LTM 300 200D MHz up to 30V m 4 1 Transmitter Sensor Tube Load Resistor Material 316ss standard optional Hastalloy Monel Kynar coated Operating Temperature 50 to 302 F 50 to 150 C Maximum Pressure 2000 psig 300 F Use twisted shielded pair of wires Race 13 10 20K 907 BAY STAR BLVD MagTlech fester tx 7759 ON OF ISE OF TEXAS INC PHONE 281 488 0788 N c APPROVED BY s s DRAWN BY ssc SECTION 5 0 Calibration 5 0 LTM 300 Output Configurations LTM 300 7200D Wiring Diagram THIS DRAWING CONTAINS PROPRIETARY INFORMATION DRAWING NUMBER PLEASE DO NOT DUPLICATE OR CIRCULATE 18032 The LTM 300 transmitter is available in three different configurations A single output version with only one variable that will output a 4 20 mA SECTION 4 Specifications signal for level The second configuration is a transmitter fitted with a second float to provide a digital output for interface level in addition to the primary level output The third configuration is one 4 20 mA signal for Primary level and two additional digital signals with one for interface Supply Voltage 15 to 36 VDC level and one for
17. been made The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Basic setup screen The user is returned to the Keypad rerange screen Note that the label above F2 is now SEND The user must press the SEND key for the HART Communicator to send the new units code to the transmitter 15 The HART Communicator will display this screen reminding the user that the loop should be removed from automatic control before proceeding When this has been done the user must press OK to continue The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Keypad rerange screen If the user has changed the unit code he may then modify the range values He selects the variable that he desires to change by using the left arrow on the highlighted line If the user selects LRV from the Keypad rerange screen the present LRV is displayed above the edit box 0 00 in as shown to the left In this example the user desires to change the LRV to 10 0 in and must press ENTER after changing the edit box to continue with the reranging of the transmitter The Keypad rerange screen now shows the new value selected by the user but the HART Communicator has not sent the command to the transmitter Note the SEND label above F2 that indicates the need to send
18. creen the user may change the LRV 4mA measurement value the URV 20mA measurement value or the Unit of measure If Unit is selected by pressing the right arrow a selection of units is available to the user If the user selects Select PV from the Basic setup screen this screen will appear reminding the user that the loop should be removed from automatic control before proceeding When this has been done the user must press OK to continue This screen will show the user that in is the current user units and the user may select from ft m in or cm When the user has selected the units that he desires by the up or down arrows he must press ENTER to continue The user must now select which variable Level or Interface will be the Primary Variable In other words which variable will control the loop current output from the transmitter In this example the user selects Interf and must press ENTER when ready to proceed After the user has selected new units he is warned that until he sends the new units code to the transmitter all variables that use this units code will remain in the previous units code The HART Communicator does not automatically send the new units code to the transmitter The user must acknowledge this message by pressing OK to continue The HART Communicator sends the command selecting the variable to be the Primary variable and the transmitter will resoond when the change has
19. etect Note Both floats have to be present for auto detection The complete assembly includes a dual compartment explosion proof enclosure and attached sensor tube Optional Features of the LTM 300 include Second digital output proportional to an interface level requires a second float of different specific gravity Digital temperature output gives the liquid temperature and is typically used for display and or calculation of mass A variety of lengths and wetted materials to accommodate many different applications Mass or Volume Information Product Serial Number Magtech assigns a unique serial number for each unit The first two digits indicate the month of production followed by two digits indicating the year of production For example serial number 0606 1234 describes a unit manufactured in June of 2006 with a serial number 1234 1 1 Level Transmitter In its simplest configuration a single purpose float rides up and down the sensor tube totally surrounding it A multi purpose float may also be used to activate the sensor such a float being placed inside a liquid isolation pipe i e Mag Gage and strategically located within a certain longitudinal distance form the sensor tube In either case the float has a somewhat lighter specific gravity than the liquid whose level is to be measured so that it is partially submerged at the interface of interest As the tank level changes the float tracks the change and continuousl
20. ew Temperature gain calibration constant When the transmitter has completed its calculation it will reply to the HART Communicator Then the HART Communicator will inform the user that the sensor upper temperature trim point has been trimmed 14 Reranging the Transmitter The user is then notified that Setting the Measurement Value for 4mA and 20mA by Keypad the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Calibration screen If you desire to change the Level value at which the Current output is 4mA and 20mA when the Level is the selected Primary Variable or change the Interface value at which the Current output is 4mA and 20mA when the Interface is the selected Primary Variable the following procedure is used The HART Communicator is now at the starting screen for the Full Temper Trim If the user selects Rerange from the Basic setup screen anew menu screen will appear with the two choices Keypad rerange and Apply Values The user will select Keypad rerange to change the 4mA and 20mA measurement values Basic Setup Procedures If a transmitter has been configured to measure both Level and Interface the Basic setup screen will display the procedure Select PV on the second line If a transmitter has not been configured to measure Interface the second line will not appear If the user selects Keypad rerange from the Rerange s
21. gned to match the pressure and specific gravity for the process being measured and come in various materials ranging from stainless steel to kynar The magnetic float can be changed out at any time to accommo date the processes being measured The float stop located at the bottom of the transmitter can be removed to allow the float to slide off the sensor tube PLEASE NOTE If using a transmitter configured for dual level output or interface measurements remember to slide the float with the lightest grav ity range first INTERCONNECT WIRING CSA amp FM HAZARDOUS AREA NON HAZARDOUS AREA ETOSTRICTIVE TRANSMITTE C L ROOM Ise Magtech Magnetostrictive LevelTransmitters LTM 300 LTM e00D Vmax 30V Imax 100mA LESS THAN 1 CHM Cl OnF SAFETY GROUND Lis S DUUH EXP NIPPLE 4 20 mA LOOP Approved Barrier MTL 5042 Single Channel SHIELD DETAIL A NOTE If the instrument is used as EXP device then the EXP conduit must be sealed within 18 of the termination point 907 BAY STAR BLVD WEBSTER TEXAS 77598 281 488 0788 MagTech CHECKED APPROVED BY DATE 01 07 02 gt S DRAWN BY SSC Cat the instrument SCALE NONE INTERCONNECT WIRING MTL MAGTECH Rev B FILE NUMBER LTM 300 THIS DRAWING CONTAINS PROPRIETARY INFORMATION DRA
22. gnostics has detected that the Level Gain constant is out of range The user should then correct this problem by trimming the Level Sensor as discussed below for the Calibration selection To return to the Diagnostics screen the user must press EXIT If the user selects View status from the Diagnostics screen the HART Communicator will send a command to the transmitter to report all of the conditions that are not normal Any status items not reported are within the normal range of operation or calibration The HART Communicator issues a command to receive the results of the transmitter diagnostics During this process the HART Communicator will ask the user to wait until the results are available Then the HART Communicator will report the results to the user in sequence In the example given here the diagnostics has detected a problem with the Level measurement that may require user intervention The user must acknowledge this problem by pressing OK to continue with the Status Also in the example given the diagnostics has detected that the Level Gain constant is out of range The user should then correct this problem by trimming the Level Sensor as discussed below in the Calibration selection The user must acknowledge this problem by pressing OK to continue with the status When the HART Communicator has completed the list of ON status bits it reports the completion of the transmitter status The
23. h to the amplifier Innovators not Imitators 3902 Magnolia Road Pearland Texas 77584 PH 281 488 0788 FAX 281 488 7080 Email magtech isemagtech com www isemagtech com
24. he HART Communicator is now at the starting screen for the Full Level Trim 13 Zero Temperature Trim Starting at the Calibration screen select the Zero Temper Trim procedure This procedure trims the Temperature digital value measurement at the reference value of the RTD 1000 ohms If the user selects Zero Temper Trim from the Calibration screen this screen will appear reminding the user that the loop should be removed from automatic control before proceeding When this has been done the user must press OK to continue This screen warns the user that proceeding will affect the sensor calibration The user must press OK when ready to proceed The HART Communicator now requests that the temperature be set to the desired 0 deg C temperature point If using a temperature simulator adjust the simulator temperature to 0 deg C or if using a resistance box adjust the resistance value to 1000 ohms The user must press OK when the RTD or simulator is at the required value The transmitter will take about fifteen seconds to insure that the temperature signal has stabilized Once the measurement is stable the procedure will continue without user intervention The HART communicator will then send the command to the transmitter to calculate the new Temperature zero calibration constant When the transmitter has completed its calculation it will reply to the HART Communicator Then the HART Commu
25. he zero reference position Full Level Trim Starting at the Calibration screen select the Full Level Trim procedure This procedure trims the Level digital value measurement at two points The first point is the position that the user desires to be the zero reference position The second point is a Level position near the end of the sensor If the user selects Zero Level Trim from the Calibration screen this screen will appear reminding srul Level Tri the user that the loop should be ji NBA removed from automatic control before proceeding When this has been done the user must press OK to continue If the user selects Full Level Trim from the Calibration screen this screen will appear reminding the user that the loop should be removed from automatic control before proceeding When this has been done the user must press OK to continue This screen warns the user that proceeding will affect the sensor calibration The user must press OK when ready to proceed The HART Communicator now reguests that the level float be set to the desired zero level trim point When the float is at this position the transmitter will always report 0 in the user chosen units The user must press OK when the float is at that position This screen warns the user that proceeding will affect the sensor calibration The user must press OK when ready to proceed The HART Communicator now requests that the level float be se
26. ingle Loop Calibration 4 5 1 On Board Menus 5 Section 6 Troubleshooting and Maintenance Page 6 0 Self Diagnostics Via HART 5 6 1 Calibration Problems 6 6 2 MagreticInterference 6 6 3 Troubleshooting Power Supply Problems 6 OF II eee a bee ue aa cease geen tea tene are eb aon heey Boe 6 Section 7 Field Insulation of Gages with Transmitters Page 7 0 Field Insulation 7 7 1 Insulation Jacket Warning Label 7 Section 8 Warranty and HART Protocol Option Page 8 0 Standard ISE MagTech Warranty 7 8 1 HART protocol Option Information 8 18 SECTION 1 Transmitter Overview 1 0 General Description The LTM 300 is an electronic field instrument suitable for installation in hazardous and non hazardous industrial areas Testing and certification has been obtained from different agencies for installation in specific areas This instrument is a two wire loop powered smart transmitter designed to measure and transmit an analog 4 20 mA signal and two digital outputs optional proportional to liquid level in a tank The optional temperature output is configured via the HART communicator Interface is auto d
27. ion utilizing the latest in integrated circuit technology It contains a high speed micro controller with a HART modem D A Converters A D Converter for optional temperature and all other accessory components 2 1 Theory of Operation The LTM 300 Level Transmitter is based on the principle of magnetostriction first used for digital delay lines and later for precision distance or displacement in the machine tool industry The principle if designed and applied properly has potentially very high measurement resolution typically better than 0 001 inch In the machine tool industry such a high resolution is desirable In the liquid level measurement application however a resolution of 0 01 inch is more that adequate In a brief description the magnetostrictive principle consists of a wire extruded and heat treated under carefully chosen conditions to retain desired magnetic properties which is pulsed by a circuit with a relatively high current pulse The high current pulse produces a circular magnetic field as it travels down the wire at the speed of light Another magnetic field generated by a permanent magnet placed near or around the wire at some distance from the point of entry of this pulse interferes with the magnetic field of the pulse and torsional force results at the collision point Waveljuide Torsion Force Wire Pulses q Fi F zA F Fa i Fa F 7 Fa i High Current c r cr 4 k 7 Pulse A ta Wa WAE
28. ions are presented If the transmitter is not configured for Temperature the Zero Temper Trim and Full Temper Trim options will not be presented The description of these procedures is given in the previous section on Calibration If the user selects Signal Condition from the Detailed setup screen he is presented with three additional selections The Keypad rerange and Apply values procedures are presented in the Rerange section The third option allows the user to modify the Level Interface damping factor If the user selects Output condition from the Detailed setup screen he is presented with two menu selections Analog output and HART output If the user selects Analog output from the Output condition screen the Alarm type is displayed and two options for procedures Loop Test and Scaled D A trim The Loop Test procedure is presented in the Diagnostics section and Scaled D A trim is presented in the Calibration section If the user selects HART output from the Output condition screen he may change the polling address of the transmitter and is given the number of request preambles required by the transmitter If the user selects Device information from the Detailed setup screen nine items are displayed and one additional menu option is displayed This portion of the list displays the items to the left The bottom half of the list of Device information items is shown to the left The menu entry Revisio
29. irst and added to the first to derive the position of the heavier float The same six inch dead zone applies to the measurement of the second level although the reasons are different This will typically correspond to a physical separation of the two floats by approximately three inches The float size geometry magnetic strength all play a factor in how close the two floats can get without interfering with each other SECTION 3 Installation and Wiring 3 0 Strap On Transmitter Installation CAUTION During installation do not attempt to twist or turn the head of the transmitter Damage to the detector assembly may occur if the head is rotated If the head is loose please notify the factory The LTM 300 can be mounted to the side of a MagTech LG series level gage using a special mounting bracket and stainless steel hose clamps When mounting the transmitter to an LG series gage the active sensor region of the probe should fall within the centerline of the process connections on the gage If the transmitter deadband region is inside the centerline of the process connections the transmitter will not output an accurate measurement because the active region of the probe is too short When placing an order for a transmitter to accompany an existing gage it is important to indicate the style of the gage the temperature and the center to center dimensions Calibration of the probe will be factory set along the active region of the probe h
30. just it to the corresponding resistance value for this temperature The user must press OK when the RTD or simulator is at the required value The transmitter will take about fifteen seconds to insure that the temperature signal has stabilized Once the measurement is stable the procedure will continue without user intervention If the user selects Full Temper Trim from the Calibration screen this screen will appear reminding the user that the loop should be removed from automatic control before proceeding When this has been done the user must press OK to continue The HART Communicator will now request the user to enter the value at the high trim point The HART Communicator will display the last upper trim point for example 100 deg C and the user will enter the new upper trim point for example 75 deg C The HART Communicator will now send this value to the transmitter This screen warns the user that proceeding will affect the sensor calibration The user must press OK when ready to proceed The HART Communicator now requests that the temperature be set to the desired 0 deg C temperature point If using a temperature simulator adjust the simulator temperature to 0 deg Cor if using a resistance box adjust the resistance value to 1000 ohms The user must press OK when the RTD or simulator is at the required value The HART communicator will then send the command to the transmitter to calculate the n
31. lly sense the interface level of the heavier of the two fluids in the tank The specific gravity of the second float will be such that it can be totally immersed in the lighter fluid Note 2 When two floats are used a minimum separation of about three inches is recommended to prevent interference between floats Single Float Transmitter Dual Float Transmitter The calibration range of the transmitter may be field stored in non volatile memory by using the float and push buttons The push buttons are located on the front panel inside the condulet See section on Calibration for more details SECTION 2 Instrument Description 2 0 Transmitter Detailed Description The LTM 300 is an assembly of two major components e The Sensor Tube Assembly This a 5 8 diameter stainless steel probe sealed on one end with the magnetostrictive waveguide in its center In addition to the magnetostrictive waveguide the tube also houses the optional temperature sensor and the detector electronics The tube is made to lengths of 2 30 ft in rigid construction e The Electronics Housing The extruded aluminum housing has two separate compartments One side contains the microprocessor board assembly and calibration push buttons The other side contains the wiring termination board The electronics module is connected to the detector board of the sensor tube assembly via a plug in cable The main board is surface mounted component construct
32. n s will display the various revisions of the transmitter If the user selects Revision s from the Device information screen the screen to the left will display the revisions of the transmitter Starting at the Sensors Screen select Zero Offset and press ENTER This procedure sets a 4mA point anywhere on the probe in reference to the end of the probe Enter the desired value of the offset from the bottom of the probe and press ENTER This will show a level offset 4mA i e 4mA will be reported 5 0 if 5 0 is selected The LTM 300 complies with the following standards IEC 60079 0 IEC60079 1 EN 50014 EN 50018 LTM300IOM Rev 6 1 18 The user must press F3 to send the Level Offset to the LTM300 Probe Length The Probe Length is set in the factory when the unit is prepared for shipment The probe length is used as a reference for a number of diagnostics fuctions as well as setting the URL and LRL shown on the Keypad rerange screens If an amplifier is changed it is important that this parameter be set to the proper value for the probe used The Probe Length parameter may be found by entering the Detailed setup menu and selecting Sensors Select Probe Length to view or edit If the probe length is incorrect provide the correct length and press ENTER When the communicator returns to the Sensors screen the SEND but ton is highlighted Press SEND to write the correct probe lengt
33. n to the previous screen the user must press OK To exit the Loop test procedure the user must select the option End and then press the ENTER key The HART Communicator then issues the command to the transmitter to return to the measurement mode as it was before entering Loop test The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Diag Service screen If the user selects Calibration from the Diag Service screen a number of menu selections are available The user must now select the type of calibration he desires to perform The Scaled D A trim will adjust the transmitter so that its current output at the 4 00mA and 20 00mA output values will agree with the plant standard current meter If it is desired to trim the digital level value he may select a single point zero trim or a full level trim that requires the input of both the zero level value and some other level value preferably near the end of the level measurement tube If the transmitter is configured with temperature measurement he may select a single temperature trim point at 0 deg Cora full temperature trim that requires trimming both at 0 deg C and some other temperature point near the upper end of the operating temperature range Output Current DAC Calibration If the user selects Scaled D A trim from the Calibration screen this sc
34. nicator will inform the user that the zero level point has been trimmed The transmitter will take about fifteen seconds to insure that the temperature signal has stabilized Once the measurement is stable the procedure will continue without user intervention The HART communicator will then send the command to the transmitter to calculate the new Temperature zero calibration constant The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Calibration screen The HART Communicator is now at the starting screen for the Zero Temper Trim When the transmitter has completed its calculation it will reply to the HART Communicator Then the HART Communicator will inform the user that the zero level point has been trimmed Full Temperature Trim Starting at the Calibration screen select the Full Level Trim procedure This procedure trims the Temperature digital value measurement at two points The first point trims the Temperature digital value measurement at the reference value of the RTD 1000 ohms The second point is a Temperature value near the upper end of the desired Temperature range The HART Communicator now requests that the temperature be set to the desired temperature upper trim point If using a temperature simulator adjust the simulator temperature to the desired temperature or if using a resistance box ad
35. nts the procedure to select the Primary variable PV if the transmitter is configured with both Level and Interface It also displays the menu that will allow the user to change the range values The procedure used to select the PV and perform the re ranging of the transmitter will be presented in more detail in the section titled Basic Setup When the HART Communicator is connected to the transmitter and turned on the first screen that is seen by the user is the root menu screen If the transmitter is configured as Level Only or Level plus Temperature the screen to the left shows the information displayed to the user If the user selects Detailed setup from the Device setup screen the next screen displays further menu selections to the user These selections will be presented in more detail in the section titled Detailed Setup However if the transmitter is configured as Level plus Interface or Level plus Interface plus Temperature and Interface has been selected as the Primary Variable Interface controls the current output the screen to the left shows the information displayed to the user Finally if the user selects Review from the Device setup screen a series of screens can be accessed that displays the value of each of the parameters of the transmitter The user may select PREV or NEXT to continue with the list or EXIT to return to the Device setup screen As the user scrolls through the list the
36. op Test Input Value This will continuously vary the loop current as the user presses the Raise or Lower buttons Exits when user depresses Select button Exit to Displays 123 45 in Level 4567 8cm 90123 mm Level 5678 9ft Level 23 45 6m Level 12 3 4 5in 32 F Temper 12 34 mA Output 56 78 Range 5 LTM300 XXX X In SelLngth in Sel U nit level Sel PV Hold Out S el Alrm No ChgRng e 12 34in Sel LR V 45 67in Sel URV Sel Damp w a v O Trn Snsr Trim Zero 123 45in Trim S pan 00 in Set Of f No TrimD ac Trim 4mA Trim 20 mA 8 OOMA LoopTest SECTION 6 Troubleshooting and Maintenance 6 0 Diagnostics are Via HART 6 1 Calibration Problems If the transmitter does not appear to calibrate properly or has an erratic output check the deadband of the sensor tube and ensure that the float is within the active region of the probe The active region of the sensor tube is typically marked with 20mA and 4mA stickers when the unit is calibrated before shipment If the output is still erratic try disconnecting the power momentarily by unplugging and re plugging in the terminals If a glitch was stored in RAM memory this will generally clear it 6 2 Magnetic Interface It is possible for the LTM 300 to be magnetically biased or have residual magnetic energy stored along the length of the waveguide These magnetic anomalies can interfere with the signal to noise ratio and
37. owever a field calibration may have to be performed to match the probe to the desired control room specifications If a transmitter is being purchased for an interface gage the calibration for the probe should be done in the field to ensure a proper control room reading For long transmitters it may be desirable for the operator to have the electronics housing mounted at the bottom of the gage for easy access THIS MUST BE SPECIFIED AT TIME OF PURCHASE Installation Note European The cable entry devices and blanking elements of unused apertures shall be of a certified flameproof type suitable for the conditions of use and correctly installed 3 1 Standalone Transmitter Installation The LTM 300 stand alone transmitter comes equipped with a 3 4 compression fitting mounted approximately 6 00 below the electronics housing The fitting is placed in this area to ensure the transmitter is calibrated in the sensor tubes active region Refer to the stand alone drawings for a visual description of the transmitter features Optional mounting configurations are available upon request The magnetic float used in the stand alone unit is designed to travel up the sensor tube with the change in fluid level If build up of process or contaminates should restrict the movement of the float the transmitter sensor tube will have to be cleaned or the float may have to be replaced with one that has a wider inside diameter The floats are desi
38. r F or C Only if configuration set to Level Temper or All Output Current Percent of Range Configuration Screens Up Down arrows choose options Press Select to Enter Model Number Model 300 Select sensor length Input overall sensor length Length end to weld Level Units rotates starting at present units gt ft lt gt m lt gt in lt gt cm lt gt mm gt PV only if Interface available rotates starting at present PV gt Level lt gt lInterf gt Alarm rotates starting at present alarm gt High lt gt Low lt gt Hold Out gt Range Change Choose Yes to Select Range Display starts with NO Lower Range Value Upper Range Value Damping From 1 to 25 Will not allow 0 or negative numbers Sensor Calibration Choose Yes to perform Sensor Trim Display starts with No Zero Trim Set float to the 4 mA mark 0 and then Select Data not required Span Trim Move the float to the 20mA mark 100 on the probe Using the arrow buttons input the correct distance from the zero point and then Select Level Offset Enter the desired value of the offset from the current zero and Press Enter This will show a level offset at 4mA i e 4mA will be reported 5 0 if 5 0 was selected Dac Trim Choose Yes to perform Dac Trim Display starts with No Dac Trim 4mA Point Press raise or lower depending on value of loop current Dac Trim 20mA Point Press raise or lower depending on value of loop current Lo
39. ransmitter this inductor emits a magnetic filed as current passes through the sensor wire If an external magnet or the float comes in contact with the bulkhead this can cause temporary magnetization of the coil which means the coil is biased In other words the phase is reversed If this occurs the inductor should quickly recover It may be manually reversed or de magnetized very simply by swiping a magnet parallel to the bulkhead in an arching motion SECTION 7 Field Insulation of Gages with Transmitters 7 0 Field Insulation We strongly recommend that experienced MagTech personnel do any insulation of the magnetic level gages with externally mounted transmitters If Cryogenic Hard Skin cold service type insulation is required it MUST be done at the factory due to the custom TUBE in TUBE design necessary for removal of the transmitter if needed If insulation is going to be done in the field then the following guidelines MUST be followed 1 Flexible type insulation jackets NOT HARD SKIN are required and must be installed around the Mag Gage chamber only DO NOT cover the LTM 300 transmitter tube as this may burn up the sensor and possibly the electronics 2 After the insulation jacket is installed the LTM 300 sensor tube must be re mounted at its factory preset distance from the Mag Gage chamber and must be parallel to the chamber as well Small cut outs in the jacket are required to re attach the
40. reen will appear reminding the user that the loop should be removed from automatic control before proceeding When this has been done the user must press OK to continue The next screen informs the user that the rest of the procedure will use the values 4 000 to 20 000 in the instructions if you are using a milliamp meter If you are using a voltmeter across a resistor select change and provide the values that you will be using at the current end points The user must press ENTER when ready The HART Communicator now instructs the user to connect the reference meter that is to be used for the current calibration The user must press OK when ready The HART Communicator will now command the transmitter to set the current output to 4 000mA The user must press OK when ready to have the current output set to 4 000mA When the device has set the current output to 4 000mA the user is to enter the reference meter reading For example if the meter actually reads 4 234mA that value is input with the keypad The user must press ENTER when the current value has been entered The transmitter based on the data from the reference meter will calculate a new value for the DAC zero calibration constant and change the output current based on the new constant If the current read by the reference meter is now 4 000mA the user must press ENTER If not exact the user must select No and press ENTER to try
41. s The LTM 300 transmitter can have as many as three outputs The first is a 4 20 mA output the second and third are digital outputs The LTM 300 is available with the following output configurations All LTM 300 Units have HART as a standard 1 Primary Level Single output version with only one variable that will output a 4 20mA signal for level 2 The second and third outputs are digital and can be configured to measure temperature and or interface level The digital outputs are read via HART 1 Primary Level Transmitter The most basic version of this transmitter is that it computes the distance between the float and the detector from the elapsed time measurement A specific time window becomes active only for a short time after the interrogation pulse is applied to the waveguide Any feedback signal received before and after this window is rejected as noise Even signals received during the active window are evaluated and filtered so that only high integrity data is accepted The conditioned signal is converted to a percent of full scale number and written to the D A Converter The scale is defined by the calibration procedure and it corresponds to the output span 4 20mA of 16 00 mA A deadband corresponding to approximately six inches next to the detector is fixed in the software and the float is not permitted to enter this area If this happens readings may be erratic or the output may go to FAIL
42. t to the desired zero level trim point When the float is at this position the transmitter will always report 0 in the user chosen units The user must press OK when the float is at that position The transmitter will take several seconds to insure that the level signal has stabilized Once the measurement is stable the procedure will continue without user intervention The HART communicator will then send the command to the transmitter to calculate the new Level zero The transmitter will take several calibration constant seconds to insure that the level signal has stabilized Once the measurementis stable the procedure will continue without When the transmitter has completed its calculation it will reply to the HART Communicator Then user intervention The HART the HART Communicator will inform communicator will then send the user that the zero level point the command to the transmitter has been trimmed to calculate the new Level zero calibration constant The user is then notified that the loop may now be returned to automatic control After the user presses OK the HART Communicator returns to the Calibration screen When the transmitter has completed its calculation it will reply to the HART Communicator Then the HART Communicator will inform the user that the zero level point has been trimmed The HART Communicator now requests that the level float be set to the desired level upper
43. the stability of the output signal itself If this appears to be the case a gage float magnet or any magnet available may be run along the length of the sensor tube past the head of the transmitter in an even motion and without stopping This will usually clear all such magnetic anomalies CAUTION Never move a magnet in a perpendicular motion from along the sensor tube This will always leave a residual field in the waveguide which will cause the transmitter to give an erratic output 6 3 Troubleshooting Power Supply Problems The LTM 300 is designed to operate with a supply voltage of 15 36 vdc at 20 mA across its terminals without affecting the mA signal The most common loop supply used is 24vdc It is found sometimes that additional resistance in the loop is necessary either in the form of a second load resistor or higher resistance safety barrier This will appear to limit the maximum output of the transmitter to below 20 mA The transmitter will generally perform correctly up to this point To resolve this problem the voltage of the loop supply must be increased somewhat Even a slight increase by one volt may be sufficient and many supplies have such an adjustment All connections must be checked for improper wiring or polarity before power is applied The LTM 300 has series diodes preventing the reverse polarity from entering and damaging the circuitry If power is applied and the signal is 0 0 mA chances are good
44. the zero point and press Secondary level is auto Enter Calibration is now completed connect Temperature is Note Sel Lngth value is factory set and should not be changed Doing saa via HART or AMS so will cause a level error indication Diagnostics On board diagnostics for troubleshooting via HART or oe ee a AMS buttons Dampening 1 to 25 seconds field adjustable via HART Oper Temp electronics 58 to 185 F 50 to 85 C Y lt Housing Explosion Proof Dual O O IA Compartment H NPT Epoxy Coated Aluminum Scroll down oe Jumper _ Write Protect Write Enable Position Polarity Protection Diode in series with the loop ASIA REVISION Hazardous Location Approvals FM Exp CI I Div Grp B C D Cl II Grp E F G CI III FRONT PANEL CSA Ex ia Intrinsically Safe CI 1 Div Grp C D Exp Expl Proof CI I Div Grp B C D CI Il Grp E F G CI Ill IECEx Expl Proof Ex d IIC T4 Atex Expl Proof EEx d IIC T4 Ex II 2 G 4 5 1 LCD Menus For The LTM 300 Displays Level Measurement Display in inches Level measurement Display in centimeters Level Measurement Display in millimeters Level Measurement Display in feet Level Measurement Display in meters Interface Measurements same decimal positions as Level Only if configuration set to Level Interface or All Temperature Measurements same decimal positions fo
45. urement points by setting the Level or Interface value in the vessel he must select Apply values from the Rerange screen If the user selects Apply values from the Rerange screen this screen will appear reminding the user that the loop should be removed from automatic control before proceeding When this has been done the user must press OK to continue The next screen gives the user a choice to set the 4mA or 20mA values or to Exit the procedure Here the user will select the 4mA menu position The HART Communicator requests the user to set the Level or Interface to the position that is to provide the 4mA loop current output When that has been done the user must press OK to continue with the procedure The HART Communicator then requests a measurement reading from the transmitter indicating the digital value at this range position The user then has the option of setting this value as the lower range value getting an update of the digital reading from the transmitter or leaving the 4mA range point as it was If the user accepts the measurement value as the 4mA loop current point the HART Communicator issues the command changing the LRV and when the transmitter replies returns to the Set screen If the user desires to change the 20mA measurement value he selects the ZOMA menu option and must press ENTER to continue the procedure The HART Communicator requests the user to set the Level or
46. value desired to perform a loop test function When the user selects the Loop test option the HART Communicator displays the warning message that the loop should be removed from automatic control during this procedure The user is presented with four selections as shown on the screen The 4mA and 20mA selections will set those values while selecting Other will require the user to input the exact loop current that is desired The procedure will be exited if the user selects End The example shows the user selection 4mA The user must press ENTER before the procedure continues The HART Communicator will then command the transmitter to set the loop current to 4mA and then it will dynamically read the value of loop current that the transmitter has applied To return to the previous screen the user must press OK The procedure is exactly the same for the 20mA selection option 10 If the user wishes to specify a loop current other than 4mA or 20mA he must select the option Other and then press the ENTER key The user must then input the exact value of loop current desired After entering the value he must press ENTER before the procedure continues For example the value 12 00 is input on the screen to the left The HART Communicator will then command the transmitter to set the loop current to 12 00mA and then it will dynamically read the value of loop current that the transmitter has applied To retur
47. y activates the sensor in the tube The electronics in the housing process the changing signal and update an analog 4 20 mA output This analog output is precisely proportional to the liquid level in the tank 1 2 Gage Mounted Transmitter The LTM 300 may be strapped to the side of the MagTech LG series magnetic level indicator In such an installation it is used as an accessory transmitter for the visual level gage The same float used to activate the magnetic gage is also used to transmit a signal to the magnetostrictive sensor of the LTM 300 In the above right shown installations the transmitters may be calibrated for the same range as the visual indicator on the Mag Gage or for part of the range See Section 3 ALLIED en cliliby lili LTM 300 Mounting Configuration Style B amp C LG Series Gage 1 3 Standalone Transmitter When a companion magnetic gage is not present the LTM 300 is inserted into the tank with its own float around the sensor tube A stilling well may be optionally used inside the tank or in case of high temperatures an external chamber may be the housing of the tube and float assembly Note 1 When a stilling well is used care should be exercised when installing the tube to center it in the chamber so that the float can freely travel the entire length of the probe Stilling wells are required for transmitters over 10 feet Up to two floats may be used with the LTM 300 The second float will typica
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