RS232/RS485 T-CHAIN User`s Manual
Contents
1. 000 21 379 000 21 315 000 21 376 042 ra 042 21 371 000 21 318 000 21 378 000 21 317 000 i 000 21 377 000 21 318 000 21 390 000 21 3179 OD O O Race O Macc acm acm D O O Ram 20202 amp I dc Im CO CO CO J CO CO CO CO OO J CO 2 1 CO 1 1 1 1 i c c NO NO NO NO cm B NO M C cn If this response does not occur check software installation and setup and check electrical connections If these are all correct contact PME o Sensors Sensor Unit of Range Initial Accuracy Stability Time Attach Measure Respon ment se deg C year seconds Oxygen whichever is greater Depth Meters 0 to 40 slope 1 FS 1 lt 5 end of 1gm cc 0 to 90 offset 5 FS seconds T 0 to 190 Chain pH pHunits 4t012 TBD J TBD j PAR umol s 0102500 5 2 m 2 second Conductivity uS cm Selectable 10 TBD lt 5 b up to seconds 200 000 TBD Ds CHLA ug l 0 5 Not calibrated 5 0 50 seconds 0 500 Temperature Temperature sensors are molded onto the T Chain They have available response over the 2 to 36 degree C range However they are normally calibrated only over 0 5 to 36 degrees C Special arrangements must be made with PME when the T Chain is ordered if the sensor is to be operated below 0 5 degrees This sensor featur2. Fast Response Sensors and Systems Precision Measurement Engineering Inc www pme com RS232 RS485 T CHAIN User s Manual 2010 Warranty I YEAR LIMITED WARRANTY ON T CHAIN HARDWARE Precision Measurement Engineering Inc PME warrant that the T Chain shall be free of defects in workmanship and materials under normal use for a period of one year from the date of shipment This warranty is made only to the original purchaser In the event a LakeESP covered by this warranty fails to operate according to our published specifications return it freight pre paid to PME or an authorized Service Provider PME will repair the unit at no charge to the customer and bear the cost of return shipment Carefully pack all components as the customer is responsible for any freight damage This warranty does not apply to services or consumable expendable items such as batteries fuses and ropes required for general maintenance Equipment manufactured by other companies such as meteorology sensors solar panels etc are warranted only to the limit of the warranties provided by their original manufacturer PME makes no warranty either expressed or implied that the sensors will be operable after they are exposed to adverse environmental conditions such as bio fouling oil fouling freezing temperatures or others This warranty is void if in our opinion the T Chain has been damaged by accident mishandled altered or repaired by the
3. 25 26 1 Introduction to the T Chain The RS232 RS485 T Chain is a single cable string consisting of a small microprocessor and sensors of various types This instrument can produce both RS232 and RS485 output RS232 Is bi directional and can be directly connected to a local PC COM port or other similar platform Unless the user must operate the T Chain with over 15 meters of cable between the host computer and the T Chain RS232 communication protocol is recommended The RS485 output can travel up to 1000 meters if cabled via suitable cable but must be connected to a suitable RS485 receiver not provided by PME Most of this document reflects the use of RS232 5 232 T Chains are normally programmed to output a string of measurements in response to a carriage return sent by the host computer on the RS232 communication This allows the host computer to synchronize T Chain output RS 485 T Chans have only output connections for RS485 In this case no character can be received from the host computer RS485 T Chains are programmed to simply emit the string of measurements repeatedly as long as power is supplied The host computer will have to implement a more complex method of synchronization The T Chain is completely waterproof and is terminated in an 8 pin underwater connector This connector is waterproof but not underwater mate able The T Chain begins with the underwater connector and continues via cable to a small microprocessor a
4. Connected equipment must synchronize to RS 485 T Chain output by software examination of the character string being received from the T Chain Software will empty it s input buffer It will then receive characters until a carriage return followed by a line feed are received Characters arriving thereafter will be placed into the input buffer until the next carriage return followed by a line feed character are received Connected software will then parse the buffer based upon the space characters or based upon column numbering into sub strings of single numbers and convert these ASCII representations into float or double types for storage within the connected equipment 5 Electrical Requirements The T Chain requires no less than 9 VDC and no greater than 20 VDC Input voltage should not contain substantial high frequency variation The measurement of temperature within the T Chain is done using thermistors shielded within inconel tubes These tubes are not connected to the electric ground within the T Chain for corrosion reasons These tubes therefore take on the electrical potential of the surrounding water There is a very slight capacitive coupling between the tubes and thermistors It is important therfore that the electrical potential of the surrounding water be maintained the same as the electrical potential on the T Chain ground T Chains without pressure transducers have a ground contact located at the end of the chain This is normally suff
5. TNode1 IEEEA Sample 1 2 4 Sample 1 ONode IEEE4 Sample 1 PNode IEEE4 EndTable M A N Main Program BeginProg Splitter CHR 32 amp CHR 32 amp CHR 32 scan 2 Sec 0 0 PanelTemp PTemp 250 Battery Batt_volt serialOpen COMME 9600 0 0 10000 SerialOutput CHR 13 serialOut COMME SerialOutput 0 1000 Serialln Seriallnout COMME 10 13 400 TrimString Trim Seriallnput amp Splitter SplitStr Split 1 TrimString Splitter 4 5 TNode1 Split 1 Converts number into engineering unit TNode2 Split 3 Converts number into engineering unit ONode Split 2 Converts number into engineering unit PNode Split 4 Converts number into engineering unit CallTable Test NextScan EndProg Hardware Installation This section describes how to install a PME T Chain I O cable assembly into a Campbell enclosure and how to connect the T Chain to the CR1000 data logger The CR800 series and CR3000 data loggers have the same connections It assumes that the Campbell enclosure has the 1 7 diameter standard hole that Campbell uses for its sealable conduit The 6738 RS 232 T Chain I O Cable Assembly can also be used with a 1 diameter custom drilled hole In this case the washers are not installed INSTALL THE BULKHEAD CONNECTOR TO THE ENCLOSURE Remove the Campbell PVC pipe fitting from the hole punched in the bottom of the logger enclosure Inside the enclosure is a threaded cap that can be unscrewed
6. appear xj raw Chain Enter details for the phone number that you want to dial Country regiory United States of America 1 Area code nz Fhone number Connect using M Cancel In the Port Settings dialog box select 9600 in the Bits per second drop down box 8 in the Data bits drop down box None in the Parity drop down box 1 in the Stop bits drop down box and None in the Flow control drop down box Press OK COM1 Properties 3 E x Port Settings Bits per second Data bits Parity Mane Stop bits 1 Flow control None Restore Defaults Ea Cancel select File Save This will save your connection so that it can be reloaded at a future time Plug the T Chain 9 pin connector into the COM port connector Supply between 9 and 12 Volts to the red and black power wires from the T Chain bulkhead connector assembly Connect to the red wire to the black wire Upon connection the T Chain should print a banner Thereafter it will print a string of measurements in response to the Enter key press on the computer s keyboard The screen shot below is an example of what will be presented The exact display will depend upon the number and type of sensors on the T Chain SCAMP HyperTerminal E o x File Edit View Call Transfer Help 012 5 3 cls e PRECISION MEASUREMENT ENGINEERING REVISION 2 0M Temperature Chain SN0012
7. customer where such treatment has affected its performance or reliability In the event of such treatment by the customer costs for repairs plus two way freight costs no COD shipments will be accepted will be borne by the customer In such cases an estimate will be submitted for approval before repair work is started Items found to be defective should be returned to PME carefully packed as the customer will be responsible for freight damage Incidental or consequential damages or costs incurred as a result of the product malfunction are not the responsibility of PME For all warranty or non warranty returns please obtain complete and submit a RMA to PME This RMA form may be obtained at http www pme com HTML9o20Docs RMAform html After submission of this from PME will respond with a RMA number Please place this number on all shipments and related communications Revision History Date Revision Description C E CONTENTS l Introduction to the T Chain 2 Quick Test 3 Sensors 3 1 3 2 3 3 3 4 3 5 3 6 lemperature Dissolved Oxygen Depth PH PAR Conductivity 4 Connections amp Communication 5 Electrical Requirements 6 Depl 6 1 oyment Rope Shackles Thimbles Float Chain Anchors Attachment to T Chain Retrieval Rope System Weight Other Moorings T Maintenance Appendix 1 Re Programming Appendix 2 Connecting to a Campbell Scientific Logger 12 16 19 20 24
8. electrically harm the T Chain Check for debris inside the dummy plug and on the outside of the bulkhead connector Clean the surfaces if required wipe with a napkin or paper towel Debris can lead to a bad seal between the plug and bulkhead Note that pin 1 of the bulkhead connector is larger than the rest of the pins Pin 1 will align with the dots on the outside of the dummy plug Align the dummy plug with pin 1 of the bulkhead and slide on the dummy plug There is a notch on the bulkhead connector above pin 1 to help align the dummy plug photos below Air can get trapped inside the dummy plug so take a flathead screwdriver and carefully jam it between the plug and bulkhead threads Twist the screwdriver such that the air 1s allowed to escape photo below Next firmly press the dummy plug against the bulkhead connector making sure it is all the way against the bulkhead threads Finally install the locking sleeve for the dummy plug Slide the sleeve over the plug with the threads pointed toward the bulkhead connector away from the enclosure Once the sleeve passes over the ring on the plug then gently twist the sleeve on to the threads of the bulkhead There is no need to overtighten the locking sleeve doing so can damage it T CHAIN INSTALLATION DO NOT CONNECT THE T CHAIN TO THE BULKHEAD CONNECTOR WITH THE LOGGER POWERED These steps are similar to the ones used in the section Installing the Dummy Plug Check for deb
9. the DB 9 connector into the male to male null adapter and tighten the screws so the connector will not dislodge when pulled photo below Install the black wire T Chain power return from the T Chain cable assembly to the GROUND LUG on the logger left photo The Campbell teal colored ground wire should also be connected to this lug and to the screw below the hex nut right photo in web IF 41 IIS LASS 717123 Install the red wire T Chain Power from the T Chain cable assembly to either the 12 V or SW 12 V ports this depends on what type of power configuration you are using Back the screw off so that the tinned part of the bare wire can easily slide into place Tighten the screw onto the bare wire Gently pull on the wire to make sure it will not come out photo below o lt _ a i m M re s aoii R Uu a ct DO NOT CONNECT THE T CHAIN TO THE BULKHEAD CONNECTOR WITH THE LOGGER POWERED Doing so can electrically harm the T Chain The T Chain can also be connected to the logger using the SMD SIO1 module purchased separately from Campbell Scientific Contact them for more information DO NOT CONNECT THE T CHAIN TO THE COM PORTS The T Chain will not work with the four COM ports 1 4 on the logger Contact Campbell Scientific for more information INSTALLING THE DUMMY PLUG DO NOT DISCONNECT THE T CHAIN FROM THE BULKHEAD CONNECTOR WITH THE LOGGER POWERED Doing so can
10. 5 0 000 21 380 8 018 22 249 21 882 0 000 21 380 9 025 22 249 21 879 0 000 21 381 8 004 22 248 21 879 0 000 21 381 8 018 22 248 21 811 21 386 8 006 22 219 21 848 0 000 21 396 1 999 22 214 21 847 0 000 21 386 9 007 22 212 21 842 0 000 21 386 9 000 22 211 21 839 0 000 21 386 8 007 22 211 21 837 0 000 21 396 1 993 22 210 21 836 The ASCII string displays the output of each sensor on the T Chain in the order that the sensor is connected along the chain Y connected sensors presented at the location given by the Y connection and not at the actual location of the sensor Only numeric output is presented The units are those that are appropriate for the specific sensor Numeric output is made according to the C language statement BAINES JUST Cr 29 which produces floating point numbers in 10 character wide columns Connected equipment can synchronize to the RS 232 T Chain output by the use of the carriage return which is sent to the T Chain Connected software will first empty it s input buffer then send the carriage return character then examine the data being returned from the T Chain until a carriage return followed by a line feed character are received Connected software will then parse the buffer based upon the space characters or based upon column numbering into sub strings of single numbers and convert these ASCII representations into float or double types for storage within the connected equipment
11. PME However the T Chain does emit the units of ug l These are based upon the sensor range and are only approximate More accurate calibration must be done by the customer via a correlation of T Chain output and concurrent sampling of the nearby water This optical sensor flows light into the nearby water and measures emissions The measurement volume is quite near the surface of the sensor but there are slight measurement errors from reflections in the far field Attempt to mount this sensor with any reflecting structures not in its field of view This sensor is sensitive to fouling and should be cleaned by wiping gently by hand as often as local conditions require This sensor is not calibrated The TChain emits CHL A in ug l units 4 Connections amp Communication The table below shows the pin out of the PME T Chain underwater connector and bulkhead connector The T Chain is DCE RS 232 T Chain and RS 485 T Chain Circuit Function T Chain Connector Bulkhead Wiring Harness Bulkhead Connector Pin Connection P N6738 Power and RS232 ground RS485 ZD Power to T Chain not used not used not connected ON 7 The customer must add appropriate wiring for RS 485 connection The bulkhead connector has numbers molded next to each pin The T Chain connector is the mirror image and has pin numbers as shown in the following sketch GROUND LOOKING INTO TCHAIN CONNECTOR The communicat
12. an they do from 50 to 100 Kg Float oubsurface floats are exposed to continuous water pressure Foam floats will gradually absorb water and loose buoyancy PME recommends a hard plastic float such as shown in the picture below Chain Anchors PME recommends that anchors be constructed of plates such as are used by weight lifters These iron discs can be individually carried and large weight anchors can be assembled just prior to deployment Weights are placed in the bottom of a small boat then chained into a stack on a piece of plywood bridged over the boat bow then shoved over the side Note that care must be taken that no personnel are tangled with any rope or cable connected to the anchor at this time When determining anchor weights the weight in air must be adjusted by the buoyancy when the anchor is placed in water weights retain 87 of their air weight when placed in water Concrete depending on the type is much worse retaining perhaps only 50 of its air weight Stone is similar Attachment of the T Chain It is tempting to tightly attach the T Chain to the mooring rope If the T Chain is to be tightly attached the rope must be pre stretched PME recommends that T Chains be only loosely attached The T Chain should be passed over a thimble and secured to the float as shown in the picture above It should be then loosely cable tied to the mooring rope A lower thimble should be used and a light weight
13. connected The mooring rope will be stretched tightly when deployed and the light weight will pull the T Chain down along side Retrieval Rope A second rope should be installed from float to anchor It should be woven with a thimble and shackled at the anchor but may be simply tied at the float end There should be extra rope beyond the length from float to anchor The purpose of this rope is to haul the anchor back when the system is recovered It is true that the mooring rope could be used for this purpose but the T Chain will be attached at the time the anchor is being lifted This rope T Chain assembly can not be passed through a pulley or onto a winch If the anchor is being hauled by hand the rope T Chain will tend to be pulled against the boat rail and the T Chain could be damaged If a separate retrieval rope is used the mooring rope T Chain can be carefully lifted from the water while the retrieval rope carries the tension System Weight The entire system must sink but the float must have sufficient buoyancy to lift the T Chain The weight of the T Chain can be approximated by Total weight in fresh water grams 23 Nnodes 40 83 Nmeters Total weight in sea water grams 23 Nnodes 37 99 Nmeters Other Moorings Customer designs of moorings should include considerations such as those presented above 7 Maintenance The T Chain should be re calibrated once yearly PME performs calibration of some of the senso
14. e Install the inner washer larger washer and nut onto the cable assembly left photo Make sure the inner smaller washer fits snugly within the hole Tighten the nut very firmly by hand enough to engage the o ring seal in the connector and to resist rotation when the T Chain is plugged unplugged right photo PME does not recommend the use of a wrench since the connector will not withstand a high level of torque If a wrench is used then do not tighten beyond 40 in Ibs Over tightening will definitely break the bulkhead connector so be careful Wipe off any excess silicone around the washer REINSTALL BACKSHELL DB 9 CONNECTOR Place the DB 9 connector onto half of the backshell with the stress relief clip around the shrink tubing of the cable left photo Install the screws through the holes in the connector and onto the other half of the backshell Notice that the screws going through the holes in the DB 9 connector are not threaded the whole length of the shaft right photo Place the other half of the backshell in position on the bottom half Insert the nuts into the grooves on the bottom side and tighten the screws such that the backshell clamps down on the shrink tubing photo below ELECTRICAL CONNECTION TO RS 232 PORT DO THE FOLLOWING CONNECTION WITH ALL POWER OFF Plug the male to male null adapter onto the RS 232 port and tighten the screws to hold it in place photo below Next plug
15. es rapid time response since the actual sensing element a thermistor extends outside the potting material This thermistor is enclosed in a thin walled inconel tube This is the silver tube in the cavity in the above picture This sensor has a digital output with service electronics potted at each node Under normal use this sensor will require no cleaning PME calibrates this sensor The T Chain emits temperature in degrees Celsius units Dissolved Oxygen The Dissolved Oxygen sensor is an optode that measures lifetime based luminescence quenching of fluorescence of a thin membrane DO sensors are Y connected to the T Chain and can be removed for calibration or cleaning This sensor will require cleaning The frequency of cleaning will depend upon the amount of algae growth or other fouling The typical cleaning interval in surface layers of fresh water lakes is 1 month with longer intervals if the sensor is deployed below the photic zone PME calibrates this sensor The T Chain emits dissolved oxygen in ug l units Depth The depth sensor is typically connected at the lower end of the T Chain There are 3 ranges available 5 10 and 20 bar full scale This sensor is an absolute pressure sensor that produces depth by converting pressure into depth units using P rho g h measured pressure in Pascal 1 bar 100000 Pascal rho 7 density of pure water at 4 deg C 1000 Kg m 3 g standard accelleration of Earth s gra
16. from the outside PVC pipe Remove the backshell of the DB 9 connector connector assembly supplied by PME by unscrewing the two screws holding it together photo below Feed the DB 9 connector end of the I O cable through the enclosure s hole left photo The connector assembly is supplied with two washers already installed on the wire right photo Carefully feed the bare DB 9 connector through the metal 2 OD washer first and then through the hex nut Make sure the wires attached to the DB 9 connector do not break photo below At this time check to see if the smaller washer approximately 1 7 OD will fit within the hole of the enclosure If the washer does not fit then remove it and file or grind it down until it does Be careful not to nick the cable Alternately the hole in the Campbell enclosure can be filed a little larger If the hole is 1 diameter custom drilled then do not use washers Place a light coating of silicone adhesive PME supplied DAP Household Adhesive Sealant or similar one between the outer washer and the enclosure photo below The intent here is to seal the washer to the enclosure Be careful that no adhesive flows between the connector and the washer The connector has an o ring that accomplishes the seal at this point If the hole is 1 diameter custom drilled then do not use washers or the silicone adhesive Press the bulkhead connector and washer against the enclosure and adhesiv
17. icient but the connected equipment must also implement good grounding to the water T Chains consume electrical current from the connected power supply The amount of current does not depend on the connected voltage to a significant degree It does however depend strong upon the number and type of sensors connected The following table and notes are intended to give an approximation of the current demand which should be computed as the sum based on the sensors The actual demand should be measured when the T Chain is received oome sensors demand a continuous current Others have substantially high demands but only for brief periods following receipt of a carriage return character by the T Chain Connected power supplies must be able to supply peak current demand Normally this is not a problem for battery operated devices but if there are long wires between the T Chain and the battery their inductance may limit the peak currents Connected equipment must be designed to supply peak current demands The table below gives sensor voltage and current requirements Idle current is consumed at all times besides measurement time Measurement current is consumed at measurement time SENSOR Input Voltage Idle Current Measurement Measurement Volt mA Current Time mA second RS232 Computer 9 to 20 30 n a always on Conductivity 9 to 20 2 30 0 8 6 Deployment Deployment of the T Chain is the customer s responsibility Deployment ar
18. ion parameters are Parameter Value 9600 Bits Parity Bits Stop Bits 1 The 5 232 T Chain is Data Communication Equipment and obeys the RS232 signaling voltage protocol by supplying 5 Volts The T Chain can both send and receive Data transmission distance is greater than 3 meters using this protocol The RS 485 T Chain obeys RS 485 protocol The T Chain sends a banner each time the power is turned on RS 323 T Chains thereafter wait for a carriage return character to be sent from the connected equipment Upon receipt of this character the T Chain responds with an ASCII string of numbers and spaces terminated by carriage return and line feed characters RS 485 T Chains simply emit measurement strings while power is applied An example is shown below SCAMP HyperTerminal 10 x File Edit view Call Transfer Help PRECISION MERSUREMENT ENGINEERING Temperature Chain SN9012 REVISION 2 0M 0 000 21 374 9 005 22 298 ZI T 0 000 21 374 7 991 22 295 21 916 0 21 37 8 001 22 287 21 913 0 000 21 379 1 995 22 202 21 913 0 000 21 375 1 995 22 280 21 911 0 000 21 376 7 981 22 219 1 910 0 042 21 377 1 982 AA 21 909 0 1 983 22 214 21 908 0 000 21 318 8 013 22 268 21 906 0 000 21 378 1 992 22 264 21 907 0 000 ns FW 1 966 22 263 21 906 0 000 21 377 9 014 22 263 21 906 0 000 21 371 1 993 22 263 21 905 0 000 21 378 8 028 22 264 21 905 0 000 21 390 9 008 22 209 21 886 0 000 21 379 8 002 22 255 21 88
19. lowing picture The picture shows the main cable that extends from far left to far right a molded temperature sensor at the right a Y connection at left and a sensor in this case dissolved oxygen towards the middle Ihe picture shows a common installation of a sensor However the cable from the Y point to the sensor can be made longer In this case the sensor ca be re positioned along the main cable Depth Pressure Sensors can be positioned along the cable but often they are placed at the very bottom of the T Chain Depth Sensors are the only sensors that are designed to be placed at the end of the cable The TChain emits a string of numbers that are separated by spaces The sequence of these numbers is established by the sequence that sensors are connected to the T Chain An entire scan of all sensors on the T Chain is emitted on a single line with following lines describing new scans of the T Chain sensor he units of measure are described below with each sensor o RS 232 Quick Test The T Chain is supplied with a wired bulkhead connector This assembly is designed to allow the RS 232 T Chain to be quickly connected to a Windows computer for testing There is a 9 pin D connector that will plug directly into a Windows COM port There are also a red and black wire that receive power The Windows computer must have a COM port serial port and be running a suitable terminal program to view the T Chain RS232 output On Window
20. nd line ends with line feed is checked 2 Connect the T chain to the computer and turn its power on You will notice a appear on screen for 2 seconds then the PME banner will come on screen The is the monitor program waiting for an input from the keyboard Press the Enter key If you miss it just cycle power and try again 3 Once you have entered the monitor you will see the as a cursor From here you can use these commands to do various operations we need 4 Type C to get a checksum value Note the value because it will be proof that we have changed the T chain s memory 5 Type E 1100 FBFF This is the erase command You ll be erasing the memory that the t chain program 1 located in Erasing will take a couple seconds A little display will show progress on screen 6 Type C again This will prove that the memory is in fact cleaned out 7 Type U Then click in hyper terminal s command bar Transfer gt Send Text File Select the file 6358 004B T XT This will immediately start the re programming process Be sure to let it run completely to it s finish If the code stops scrolling press and hold the enter button for a few seconds You ll know when it s done when the comes back Reprogramming may take 2 3 minutes If the program has not finished loading but you are seeing FFFF press Q to exit 8 Once it s all done you can either type G or cycle the power This will start the t chain with the new program Appe
21. nd thereafter to the various sensors T Chains are always custom built to customer specifications Customers must specify the types and positions of the sensors they require Temperature sensors are directly molded onto the cable They can not be removed except by cutting and their positions can not be changed Other sensors are however fitted to the T Chain via short lengths of spur cable that make Y connections to the main cable These sensors can be removed and if sufficient spur cable length is available moved to different locations along the main cable T Chains are designed to be secured by cable ties to some other support T Chains are supplied with a wired bulkhead connector This assembly allows quick connection to a PC COM port for initial tests of the T Chain In some cases such as connection to a Campbell data logger within a Campbell enclosure this wired bulkhead connector can be used directly In general the customer will after testing disassemble the bulkhead wiring and install whatever is necessary for the specific application oensors are connected to the T Chain in three ways e Molded onto the T Chain at permanent locations e Y onto the T Chain e Connected at the end of the T Chain Temperature sensors are the only permanently molded sensors on the T Chain The following picture shows a temperature sensor There are several other sensors that Y onto the T Chain In general the sensors are as shown in the fol
22. ndix 2 Connecting the RS 232 T Chain to a Campbell Scientific Logger With the use of a Campbell SC32B adapter real time T chain data can be displayed With the program shown below the CR1000 can operate the T chain and then parse the data string to display each sensor s data Then with the use of LoggerNet real time charts can display the incoming data The picture below shows a graph of the 2 temperature sensors that are installed on the T chain 61 CR1000 Graph 1 Real Time Monitoring Connected Selected Fields Node1 23 00 TNode2 22 68 Add Delete Graph Width 0d 00h 02m 005 ES rawing Mode Strip Chart C Shift Data o ad Options Clear Rescate 4 15 2008 2 40 20 Delete Graph Width 0d 00h 02m 005 a rawing Mode Strip Chart Shift Shift Data E 4 15 2009 2 30 50 4 15 2009 2 31 20 AM 4 15 2009 2 31 50 4 15 2009 2 32 20 AM 4 15 2009 2 32 50 CR1000 Series Datalogger PME T Chain Operator date 16 APR 2009 program author Garren Declare Public Variables Public PTemp batt_volt TNode1 TNode2 ONode PNode Public SerialOutput As String 25 Public Seriallnput As String 50 Public TrimString As String 50 Public Split 4 As Long Public Splitter As String 20 Define Data Tables DataTable Test 1 1 Datalnterval 0 10 Sec 5 Minimum 1 batt volt FP2 0 False Sample 1 PTemp FP2 sample 1
23. r calibration PME does not perform calibration of this sensor but implements the calibration supplied by LiCor The T Chain is supplied with the PAR sensor connected and operational However the sensor must be attached to the T Chain by the customer since the attachment bracket is too large to be conveniently shipped The customer will provide PVC cement for this purpose The customer must glue the pipe supplied by PME as shown in the picture below The sensor bracket is then attached to the T Chain by threading cable ties through the holes in the bracket and securing them to the T Chain cable The TChain emits PAR in umol s m 2 units Conductivity The conductivity sensor is a electrode less sensor The range of this sensor is selectable The sensor is useful in salt water situations such as estuaries where location of the transition zone is desired The sensor lacks sensitivity for normal fresh water lake use but has sufficient range for sea water and hyper saline lakes The range of the sensor should be provided to PME at the time the T Chain is ordered PME calibrates this sensor The T Chain emits conductivity in uS cm CHL A The CHL A sensor is a Turner Designs Cyclops 7 optical sensor that has been adapted to PME s T Chain This sensor has 3 ranges A range must be selected prior to installing on the T Chain Sensor range can not be changed thereafter without disassembling the sensor CHL A sensors are not calibrated by
24. rangements should be designed so that the T Chain never is tensioned It is difficult to anticipate all the possible deployments that customers might use However one simple example depolyment is a bottom anchor with a sub surface float This example will be discussed below to point out common problems and solutions The table below shows a bill of materials for a typical sub surface buoy mooring These are discussed subsequently ty Used 55 tchain rope 12 strand polyester 3 8 x600ft 182m 5 thimble 3 8 316ss heavy duty for tchain rope 1 Float subsurface 45 20kg lift 14 plastic 1 5 meter Chain 1 4 316ss around anchors 40 cable ties 7 inches black UV stabilized nylon 40 Ib 3 shackle 3 8 316ss D wide 1 weight 2 5kg 5 Ib plate lower end of T Chain 2 weight 25 Kg 50 pound plate anchor Rope Shackles Thimbles Multi strand rope with good UV resistance is recommended Thimbles should be used at each end to resist abrasion as the mooring flexes due to water motions Multi strand ropes should be used since theses can be braided to form very strong connections to the thimbles as shown in the picture below Two types of shackles are listed in the table depending on where they are used Rope manufacturer s provide elongation under tension specifications but beware that these specifications often do not include initial weave compression Ropes can stretch significantly more from 0 to 50 Kg tension th
25. ris inside of the underwater connector and on the outside of the bulkhead connector Clean the surfaces if required wipe with a napkin or paper towel Debris can lead to a bad seal between the underwater connector and the bulkhead connector Note that pin 1 of the bulkhead connector is larger than the rest of the pins Pin 1 will align with the dots on the outside of the T chain s underwater connector Align the underwater connector with pin 1 of the bulkhead connector and slide on the underwater connector There is a notch on the bulkhead connector above pin 1 to help align the underwater connector Air can get trapped inside the underwater connector so take a flathead screwdriver and carefully jam it between the underwater connector and bulkhead connector threads Twist the screwdriver such that the air 1s allowed to escape Firmly press the underwater connector against the bulkhead connector making sure that it is all the way against the bulkhead threads Finally slide on the locking sleeve for the underwater connector Once the sleeve passes over the ring on the underwater connector gently twist the sleeve on to the threads of the bulkhead connector There is no need to overtighten the locking sleeve doing so can damage it OVERALL VIEW INSIDE ENCLOSURE
26. rs but others such as PAR must be returned to the manufacturer for calibration Customers can not re calibrate T Chains These must be returned to PME for re calibration Oxygen sensors located in the photic zone should be cleaned by gently brushing or wiping the sensing point This should be done monthly or more frequently depending on local conditions Conductivity sensors should be wiped clean from time to time depending on local conditions pH sensor service interval is yet to be determined Appendix 1 Reprogramming The RS 232 T Chain The T Chain contains a small microprocessor running a program that coordinates sensor measurements calculates engineering units and produces the RS232 RS485 output This program can be changed thru the RS232 communication but not thru the RS485 communication since RS485 has only output Each time that power 15 applied to the T Chain it waits a brief period before beginning the sensor program If during this time any RS232 input is received from the host computer the T Chain will enter a different part of the program called the monitor that implements loading features PME will supply the new program customer can not create programs Follow the instructions below to install the new program 1 Open Hyper Terminal and adjust the Comm setting to 9600 baud 8n1 Once the terminal is setup In File gt properties gt settings ASCII Setup change Line Delay to 50 milliseconds Make sure Se
27. s 2000 and XP the terminal program Hyperterminal may be found under start Accessories Communications Hyperterminal For later Windows operating systems Hyperterminal can be purchased from http www hilgraeve com hyperterminal An alternate terminal program can be obtained free at http realterm sourceforge net In addition to a communications program the Windows computer must have serial COM port Most modern laptops lack this port A USB to serial adapter not supplied by PME can be purchased for a small cost In general these must be physically plugged into the computer USB port and the software properly installed prior to using Hyperterminal or another communications program Follow the manufacturer s installation instructions The T Chain communicates via a RS232 5 V protocol at 9600 Baud 8 bits no parity 1 stop bit Hyperterminal must be set up for T Chain communication Run Hyperterminal select File New Connection A Connection Description dialog box will appear In the Connection Description dialog window enter LakeESP in the Name box then press OK Connection Description 2 Connection Enter a name and choose an icon Far the connector MH ama T Chain A Connect To dialog window will appear Select the correct COM number for the laptop usually COM 1 or the USB adapter could be COM 3 or COM 4 or other from the Connect using drop down box Press OK A Port Settings dialog box will
28. vity 9 80665 m sec 2 h the depth in meters Since the depth sensor is an absolute device it senses atmospheric pressure as well as the pressure of the water column Normally the T Chain output is as shown above and it is left to the user to adjust the value produced for local atmospheric pressure the actual average density of the water column and to adjust for variation in barometric pressure if desired PME calibrates this sensor In actual use the deployment distance of the pressure transducer will be somewhat uncertain and will depend upon things such as the depth that the system anchor sinks into the sediment The normal procedure will be to deploy the sensor measure the depth adjust the sensor output by water column density and then add a constant number to give the correct initial depth PME calibrates this sensor The TChain emits depth in meters of water assuming 1 gm cm 3 density units pH The pH sensor is a SensorEx S222CD sensor which PME mounts digitizes and connects into the T Chain The S222CD is a sealed double junction pH sensor The sensor is inexpensive and can be replaced in PME s mounting saving the cost of replacing the mounting PME performs the calibration of this sensor using 3 standard solutions The PAR Photosynthetically Active Radiation sensor is a Li Cor LI 192 sensor which PME mounts digitizes and connects into the T Chain This sensor must be dismounted prior to return to Li Cor fo
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