File - Solartron Metrology
Contents
1. 1 Set the transducer core to the null position If this cannot be determined mechanically then with no OFFSET resistors connected adjust the core position for a OV output 2 Connect temporary SOT or variable resistors leads to be kept as short as possible as shown for the required polarity offset Fig 3 6 a for a positive offset and Fig 3 6 b for a negative offset Resistance Box Resistance Box b POSITIVE OFFSET NEGATIVE OFFSET Fig 3 6 Temporary Resistor Connections Offset 3 0 Operational Guide c OO 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit 3 Adjust the variable resistance until the required offset is achieved 4 If a single resistor is to be fitted fit a NPV fixed resistor to position R4 or R4 Fit a wire link to position R3 If two resistors are to be used for a more accurate calibration see step 5 5 Fit a resistor with NPV that is just below the required value to position R4 or R4 Re connect the temporary variable resistor to position R3 6 Repeat steps 1 amp 3 moving the core between the null position and the full scale position adjusting the variable resistor as required to achieve the required output 7 Substitute the temporary variable resistor for a fixed resistor of the nearest preferred value 3 0 Operational Guide A 5 A_wxqxcrcaaaa 501651 Issue 14 1 4 0 The Case The BICM case comprises two identical halves which are simply cl2. at least 13 5 VDC at the power supply pads of the bipolar or 21 6 V for unipolar BICM Is there a proper OV connection Transducer Is the transducer core able to move the required amount Setup Is gain and offset set correctly Have the components been fitted properly any dry joints WRONG POLARITY OUTPUT Transducer Secondary connection wrong way round swap white and green wires Set up Voltmeter indicator connected wrong way round 5 0 The Why Doesn t it Work Guide 9 rer 501651 Issue 14 1 6 0 Application Notes 6 1 Transducer The MACH 1 5 kHz Series range of Transducer coil assemblies are designed for protection against dust and water to IP66 making them suitable for use in harsh environments Designed to be rugged and yet still cost effective these devices offer the Customer all the attributes associated with LVDT s A variety of combinations and accessories are available as options 6 1 1 Introduction The MACH 1 5 kHz Series range of transducers operate on the LVDT principal where movement of a core inside the transducer body is detected by a differential change in output on two secondary coils the primary coil s being energised by an appropriate AC signal With the core in a central position the coupling from the primary to each secondary is equal and opposite and therefore cancel out thus the resultant output voltage is zero As the core is displaced further into one secondary its voltage increases proportionally and
3. Connect the transducer to the BICM according to Fig 3 1 Connect the output BICM to the display instrument in this case a voltmeter on the DC range as shown in the diagram of the last example Move the transducer core to the approximate null position half way along the transducer bore Turn the power supply on A small output will probably be indicated on the voltmeter unless the core and OFFSET potentiometer are exactly at null If the offset pot has already been fitted see USEFUL HINTS 4 Adjust the core position until the voltmeter reads OV Move the core 2 5 mm inwards from the null position The voltmeter should show a positive increase in output Adjust the GAIN potentiometer clockwise until 2 5 V is indicated on the voltmeter Move the core back to the null position then repeat 6 to 8 until satisfied with the calibration Move the core 2 5 mm outwards and check that 2 5 V is indicated on the voltmeter The transducer has now been calibrated for 2 5 V for 5 mm of movement 10 Fit the 5 k potentiometer to the GAIN position on the BICM board and set the potentiometer to the approximate mid position 6 0 Application Notes 0 501651 Issue 14 1 6 0 Application Notes 6 3 Example 2 continued 11 For a 0 to 5 V output simply adjust the OFFSET potentiometer until the 2 5 V reading on the voltmeter shows OV If the core is moved to the mechanical null position 2 5 V should be indicated and 5 V at the fully o
4. Solartron Metrology BICM LVDT Boxed Inline Conditioning Module For LVDT Transducers only user leaflet AMETEK ULTRA PRECISION TECHNOLOGIES Index Section Title Page MAGNE o tad dt a a e ete abd i 1 0 Introduction 00 a tw we ae e 2 2 0 Technical Specification 3 3 0 Operational and Set Up Guide BICM Kit 6 el MEO e oa ao is as de arto 3 2 Screen Connection 3 3 Gain Adjustment 3 4 Offset sey 3 5 Set Up Using Fixed Value Resistors 11 3 6 Gain Set Up Procedure 13 3 7 Offset Set Up Procedure 14 4 0 The Case cies hinges seers i A 16 5 0 The Why Doesn t it Work Guide 17 6 0 Application Notes isas isina eee ere ee 18 6 1 Transducer Installation 18 6 2 Example 1 6 3 Example 2 Return Of Goods Solartron Sales Offices Index O0 501651 Issue 14 1 1 0 Introduction 1 0 Introduction amp Glossary The Boxed Inline Conditioning Module BICM is an electronics module that may be used with a wide range of LVDT transducers Layout and size are designed to allow the BICM to be easily fitted inline with the transducer cable and installed with the minimum of effort or changed if ready connected to a transducer The BICM output may be set for a full scale range up to 10 VDC offset facilities are provided The BICM is either powered from a bipolar 15 VDC supply or a unipolar 24 VDC supply depending on product typ
5. amped around the PCB and connecting cables Four self tapping screws are used to secure the halves together Please note each half has a step along the side The case halves will only mate correctly one way round DO NOT OVER TIGHTEN THE SCREWS when reassembling the case The strain relief blades in each half of the case may be removed if not required If enhanced environmental protection is required it is recommended that a suitable adhesive sealant is applied to all edges of the case before assembly A suitable potting agent may also prove effective T T C Strain Relief l a D D Fig 4 1 Case Assembly 4 0 The Case A E ETE 501651 Issue 14 1 5 0 The Why Doesn t it Work Guide This is not an exhaustive list of problems but may help cure some of more common problems FAULT CONDITION POSSIBLE CAUSE OF FAULT NO OUTPUT Power supply Is it connected correctly Is it turned on Is there at least 13 5 VDC at the power supply pads of the bipolar or 21 6 V for unipolar BICM Transducer Is it connected correctly Is the transducer functional perform continuity tests SUPPLY CURRENT HIGH Power supply see NO OUTPUT Transducer Core not in transducer Short on primary connection Short on secondary connection Is the transducer functional perform continuity test Is the primary drive to transducer correct compare with specification Output load Is the output shorted or wrong load INSUFFICIENT OUTPUT Power supply Is there
6. cification limits assume a nominal 3 m cable length between transducer and BICM The BICM can be mounted up to 10 m from the transducer but this may result in reduced performance Not all transducers can cope with long cable lengths Cable from the BICM to the processing unit or display should be limited to 100 m 2 0 Technical Specification 0 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit 3 1 Introduction The BICM kit is supplied with a selection of potentiometers and an output cable allowing users to connect LVDT sensors and set up to their own requirements Connections are made to the BICM PCB as shown in Fig 3 1A or Fig 3 1B below depending on the PCB version The BICM output is adjustable for GAIN and OFFSET See the specification for range of adjustments possible Gain is sometimes called span or range This control will affect the output voltage at the full transducer stroke Adjusting the control clockwise will increase the output Offset is sometimes called DC shift or zero shift This control may be used to zero the output if mechanically nulling the transducer is not convenient or can provide as much as 100 offset to enable the output to be unipolar ie OV to 10 V for full transducer stroke Adjusting the control clockwise will make output more negative Adjustment is by means of trimmer potentiometers also called variable resistor or pots The BICM will accept fixed value resistors in place of potentio
7. e Ensure that your product is wired up correctly see section 3 Ensure that you do not apply greater than 15 V to either of the bipolar supply inputs BICM Boxed Inline Conditioning Unit Gain The output voltage per mm of transducer stroke Offset The output voltage when the transducer core is at null P C B Printed Circuit Board NPV Nearest Preferred Value A resistor selected from a standard range of value E24 E48 etc that is closest to the required value BICM kits are supplied for user connection to an LVDT transducer 2 0 Introduction 0 501651 Issue 14 1 2 0 Technical Specification a E O Y Co PS E e Pere E ANNIE TT Ce IS EN A Primary Frequency 1 5 kHz typical A Primary Current 10 mA nominal A Input Voltage Range Up to 2 5 Vrms A Input Load Resistance 100 kQ 2 0 Technical Specification 0 501651 Issue 14 1 2 0 Technical Specification TO O O Y 7 CO A EN EC IN TT VAN Pemon DEN Ce Pow p o ES EC Pros Pro 22 e MN CCOO INN TOS 1 Other frequencies are available on request 2 The electronics has a specification of lt 0 1 the overall linearity is dominated by the transducer 3 Other bandwidths available on request 2 0 Technical Specification 0 TG 501651 Issue 14 1 2 0 Technical Specification ANIOS NENE T CON O Y ICC IN EEN BC BE CCS Ps 22 C IO NN EC INN 7777 TON Tersvesie Pens Ps 22222 gt gt Cable Lengths All spe
8. e at the PSU but it all depends on the installation requirements Colours are for Solartron MACH 1 5 kHz Series transducers Check individual transducer data sheets before connecting If a different polarity output is required secondary connections may be reversed See application notes Centre Tap CT yellow wire connection not required Ensure no loose wires 3 2 Screen Connection Fit the potentiometers in the positions indicated in Fig 3 3 The table below gives suggested values for use with some solartron LVDT s Once fitted the set up procedure can be followed to give the required output 3 0 Operational Guide Qa Am Sea 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit TRANSDUCER POTENTIOMETER VALUE ohms GAIN OFFSET B2 5 100K 5K B5 0 50K 10K B10 100K 5K B15 100K 5K B25 100K 5K B50 50K 10K B100 50K 10K GAIN RVI NIYI Aa Top View Transducer Ta Connection End Side View RA IRIM POT FITMENT BENO LEAOS S0 BEFORE FITTING 135340 Fit this way round OFFSET RV2 Fig 3 3 Component Installation 3 0 Operational Guide 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit 3 3 Gain Adjustment Gain adjustment is best done before offset adjustment If an OFFSET potentiometer has been fitted then set this to the mid position GAIN SETUP PROCEDURE 1 Adjust the potentiometer to the approximate mid position about 12 full turns from either
9. e box to the board as in Fig 3 5 a Set the resistor to an initial value as shown in the table Resistance Box Resistance Box Fig 3 5 Temporary Resistor Connections Gain 2 Move the core to a full scale position either inwards ve output or outwards ve output Adjust the potentiometer value to give the required full scale output voltage such as or 10 V 3 Move the core to the full scale position Adjust the variable resistor value to give the required full scale output voltage such as or 10 V 4 Return the core to the null position and check the output Repeat steps 2 amp 3 as required 5 If a single resistor is to be fitted fit a NPV fixed resistor to position R1 Fit a wire link to position R2 If two resistors are to be used for a more accurate calibration see step 6 3 0 Operational Guide A ga T m 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit 6 Fit a NPV fixed resistor that is just below the value required to position R1 Reconnect the temporary variable resistor to position R2 see Fig 3 6 b 7 Repeat steps 2 amp 3 moving the core between the null position and the full scale position adjusting the variable resistor as necessary to achieve the required output 8 Substitute a NPV fixed resistor for the temporary variable resistor position R2 3 7 Offset Set Up Procedure It is assumed that the gain has been set up consistent with the overall required result
10. end 2 Adjust the LVDT core position to give OV output 3 Move the core to a full scale position either inwards ve output or outwards ve output Adjust the potentiometer value to give the required full scale output voltage such as or 10 V Adjusting the control clockwise will increase the output 4 Return the core to the null position and check the output Repeat steps 2 amp 3 as required 3 4 Offset Any offset required is set by simply adjusting the OFFSET potentiometer until the required positive or negative offset is achieved Adjusting the control clockwise will make the output more negative Example Output required is OV to 8 V for full transducer stroke fully out to fully in Set the gain for an output of OV 4 V then apply an offset of 4 V Applying the required offset can sometimes be difficult if the gain is not correctly set The application notes may help If no offset is required it is best not to fit the OFFSET potentiometer 3 0 Operational Guide _ _ aoa _JH ea 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit 3 5 Set Up Using Fixed Value Resistors Fit the components into the positions shown in Fig 3 4 once component values have been determined using the set up procedure The term nearest preferred value NPV is used throughout This is a resistor selected from standard ranges E24 E48 etc that most closely matches the value required Two resistors in series may be fit
11. er to the BICM according to Fig 3 1 4 Connect the output BICM to the display instrument in this case a voltmeter on the DC range as shown in Fig 6 1 2 01311 visir vomere scm po SOLARTRON Power Supply HSY or Sore B15 Transducer gt lt 15mm 15mm Unipolar supply connections shown Fig 6 2 5 Move the transducer core to the approximate null position half way along the transducer bore 6 Turn the power supply on A small output will probably be indicated on the voltmeter unless the core has been placed exactly at null 6 Adjust the core position until the voltmeter reads OV 6 0 Application Notes sSNA err 501651 Issue 14 1 6 0 Application Notes 6 2 Example 1 continued 7 8 9 Move the core 15 mm inwards from the null position The voltmeter should indicate a Positive increase in output Adjust the GAIN potentiometer clockwise until 10 V is indicated on the voltmeter Move the core back to the null position then repeat steps 6 to 8 until satisfied with the calibration Move the core 15 mm outwards and check that 10 V is indicated on the voltmeter 6 3 Example 2 B2 5 TRANSDUCER 2 5 mm stroke 5 mm total stroke BICM output 0 TO 5 V OUTPUT OVER 5 mm ie 2 5 V output plus 2 5 V offset 1 2 3 4 5 8 9 9 Fit the 100 k potentiometer to the GAIN position on the BICM board The OFFSET potentiometer will be fitted later
12. hread for attachment to the fixture 6 1 5 Guided Carrier MOUNTING Normal mounting methods apply see section 6 1 2 on Installation Careful consideration should be given to alignment the carrier must be able to move freely within the transducer core Side force should be kept to a minimal level MAINTENANCE Check for free movement of the carrier when in the vertical plane Lubrication is provided via an oilite bush which is impregnated with molybdenum disulphide and in normal usage is maintenance free 6 0 Application Notes _ 1 l OO_TcT 501651 Issue 14 1 6 0 Application Notes 6 1 6 Ball Tip This option is for use with the Guided Carrier and is attached via an adapter fitted to the threaded end of the core carrier Side forces which may exert undue pressure and flex the carrier must be avoided 6 1 7 Rod End Bearings MOUNTING With the exception of the B100 the Transducer may be mounted in an axis it is recommended that the rear rod end bearing near cable exit is mounted on the static component The B100 because of the increase in weight may exhibit bowing of the carrier and therefore mounting in the horizontal plane should either be avoided or additional support given to the body This option is used with the guided core MAINTENANCE Rod end bearings are supplied pre lubricated with mineral oil for higher temperature applications the use of a molybdenum disulphide impregnated oil is recommended and y
13. lternative 6 0 Application Notes AS qT 501651 Issue 14 1 6 0 Application Notes 6 1 2 Installation continued Irrespective of clamping method care must be taken not to overtighten retaining screws as distortion of the body may prove damaging to the integrity of the transducer and adversely affect the geometry of the installation If the LVDT is to be mounted on equipment subject to high g then dependent on the direction of these forces it may be advantageous to consider end to end clamping in preference to over body clamping The magnetic core supplied with each transducer has been manufactured and heat treated to achieve the optimum magnetic performance any subsequent handling of the core which results in stress being imparted will render the calibration void this includes overtightening of the core during installation onto its carrier Hand tightening and retention by means of a suitable thread locking anaerobic retainer is the recommended procedure 6 1 3 Cores The standard core supplied with each transducer incorporates an M4 x 0 7 x 12 mm deep female thread at both ends for mounting onto a carrier An alternative 6 40 UNF female thread is available as a standard option upon request 6 1 4 Carriers A standard length carrier is available for each model of transducer manufactured from 316 stainless steel and incorporating an M4 x 0 7 x 10 mm long male thread for attachment to the standard core and an M4 x 0 7 x 20 mm male t
14. meters The BICM is designed to accept the following types of potentiometer or resistor Potentiometer Standard 3 8in square top adjust type potentiometer see Fig 3 1 ie Bourns 3299 type The BICM kit comes complete with four potentiometers Resistors 1 4W MRF4 style 3 0 Operational Guide AS Ai x cram 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit Secondary 2 Green Vout Yellow Secondary 1 White F Va OV Signal et white Screen 2 R2 SUPPLY CONNECTIONS FRA BIPOLAR UNIPOLAR Be 15 V 24 V S 0 Y SUPPLY 0 Y SUPPLY 15 Y NO CONNECTION Primary Exc1 Blue J Primary Exc 2 Red Fig 3 1A Connections to PCB 105186 Bipolar or Unipolar Green sec2 VOUT Output SEC1 ov Signal Screen Screen PRIM ata Primary ov Bape PRIZ Red av TRANSDUCER CONNECTIONS VO CONNECTIONS Fig 3 1B Connections to PCB 103766 Bipolar only 3 0 Operational Guide 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit 3 2 Screen Connection The screen connection is arranged so that the transducer cable screen and l O cable screen is connected and that some cable strain relief is provided whilst setting up the board Screens are not connected to OV on the PCB Screen and OV may be connected on the PCB by using a wire link or at the user connection end for exampl
15. our representative should be consulted about the maximum temperature Periodic inspection of locking screws and nuts etc is advisable depending upon the Customers application Rod end bearings should be able to move freely and have minimal side play 6 1 8 Cable Solartron Metrology cable is specially manufactured to optimise performance with respect to temperature chemical resistance flex life abrasion resistance and electrical performance However no single cable design can fulfil every known requirement and by taking a few simple precautions cable failure can be avoided In flexture conditions then a minimum bend radius of 150 mm should be maintained Avoid contact with sharp edges and rough surfaces and inspect at periodic intervals Excessive cable runs may alter the output characteristics if in doubt consult your representative 6 0 Application Notes _ mm 2 reer 501651 Issue 14 1 6 0 Application Notes IF POSSIBLE CENTRALISE L V D T NON METALLIC SPLIT TUFNOL BUSH FOR USE WITH METALLIC CLAMP Fig 6 1 Examples of Clamping Methods 6 0 Application Notes 0 501651 Issue 14 1 6 0 Application Notes 6 2 Example 1 B15 TRANSDUCER 15 mm stroke 30 mm total stroke BICM output 10 V output no offset 1 Fit the 100 k potentiometer to the GAIN position on the BICM board 2 No offset is required so the 50 k potentiometer is NOT fitted to the GAIN position on the BICM board 3 Connect the transduc
16. ted to allow for more accurate calibration of gain and offset If only one resistor is required a wire link is fitted in place of the second resistor Gain adjustment is best done before offset adjustment If an OFFSET potentiometer is fitted set this to the mid position If a resistor is fitted temporarily disconnect this If an offset is to be applied take this into account when setting the gain Example Output required is OV to 10 V for full transducer stroke fully out to fully in Set the gain for an output of OV 5 V then apply an offset of 5 V Some suggested start values for resistors are shown in the table below If the transducer being used is not in the list then start with an arbitrary value such as 50 Kohms 3 0 Operational Guide A _9VJ eee 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit TRANSDUCER APPROXIMATE RESISTOR VALUE ohms GAIN OFFSET or 5V B15 85K 20K B25 61K 13K B5 0 40K 7K5 B10 70K 15K B15 52K 11K B25 51K 11K B50 39K 7K5 B100 25K 4K3 GAIN RI R2 R3 R4 OR R4 OFFSET Fig 3 4 Resistor Positions 3 0 Operational Guide Oa ii ee 501651 Issue 14 1 3 0 Operational and Set Up Guide BICM Kit 3 6 Gain Set Up Procedure If this procedure is to be used to determine the value of potentiometer required perform up to step 6 The potentiometer value will be the NPV greater than the resistor value determined 1 Temporarily connect a variable resistance such as a decad
17. the other secondary voltage decreases hence the output changes in magnitude and phase in proportion to movement in either direction from null The red and white connections are in phase for inward movement ie towards the cable end The output signal depends on both core movement and energisation voltage and is expressed as a sensitivity in mV output V energising mm travel 6 1 2 Installation LVDT transducers generally are a reliable and proven technology that is well established in all areas of manufacturing and control industries The majority of the associated problems experienced with their application and use are totally avoidable particularly if sufficient thought is given during the initial design stages of equipment to the positioning and clamping methods employed for these feedback elements LVDT s being of inductive nature are susceptible to some degree to the influence of magnetic fields and therefore should be positioned well away from electric motors relays and permanent magnets where this is not possible then magnetic shielding should be considered as an alternative Clamping of the coil assembly should be carefully considered some example methods are shown overleaf Ideally the body of the transducers should be clamped centrally in a pinch or yoke type clamp manufactured from a low conductivity non magnetic material if this is not possible then the introduction of a non metallic bush between body and clamp is a preferred a
18. ut position 6 4 Some Useful Hints 1 If no offset facility is required it is best not to fit any OFFSET components This makes calibration much easier 2 If an opposite polarity output is required ie a ve output for an inward core movement the secondary connections to the BICM may be reversed white and green wires for a Solartron MACH 1 5 kHz Series transducer 3 If the BICM is to be placed in a position where it may be subject to high levels of vibration then using resistors for calibration is advised as potentiometers may shift 4 If an offset potentiometer is fitted an accurate electrical null can easily be found Put a temporary shorting link across the transducer secondary by connecting the SEC1 and SEC2 pads on the BICM board Adjust the OFFSET potentiometer to give an accurate OV on the voltmeter Now remove the temporary short Best performance will be achieved if resistors are used to set gain and offset Potentiometers whilst being of high quality have a poorer temperature coefficient than resistors Output noise and stability are also improved by using resistors 6 0 Application Notes A 2 ac cTrcaaaa 501651 Issue 14 1
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