background image

12 | 

P a g e

 

 

 

Need Help? Email 

[email protected]

 or visit www.gropoint.com/support

 

 

RIOT Technology Corp.

 | #220

10114 McDonald Park Rd | North Saanich V8L5X8, BC Canada | +1.250.412.6642  

www.riotwireless.com

 

www.gropoint.com

 

 

All Rights Reserved 

©2020,

 

RIOT Technology Corp. 

Special Notes Regarding Profiling Probes of 4 or More Segments 

GPLP Lite Profiling probes with more than three segments have special requirements for com-
municating. Internally, these probes consist of several circuit boards daisy chained together: A 
four-segment probe has two daisy chained 2-segment boards. A six-segment probe has two 
daisy chained 3-segment boards. The first board ordinarily handles all normal communications, 
particularly handling of all basic SDI-12 commands.  

When necessary, there is a specific mechanism and requirements for sending commands di-
rectly to attached daisy chained boards and some special cautions must also be employed. In 
particular: 

 

Power to daisy chained boards is normally off and must be specifically turned on first 
with the 

aXSA! 

command. A start up delay of at least 150 ms must occur after this 

command before sending any further commands to the daisy chained board. 

 

All measurement commands automatically turn off power to daisy chained boards to en-
sure the sensor returns to low power state, so if additional commands are to be sent af-
ter a measurement the aXSA! command must be resent to turn power back on. 

 

Commands to a daisy chained board are embedded in the following special extended command 
format: 

aXn

command

where n is the position in the daisy chain. “1” is for the first attached board (segments 3 and 4

 

in a 4-segment probe), 2 is for the second attached board (usually only with 8-segment probes) 
etc. The 

command 

can be any valid SDI- 12 command, including extended commands. Each 

board in the chain includes its address in the response. For example, to get the ID string for the 
first attached board (when the main sensor has address 0) send the command 

0X1I! 

The re-

sponse will be 

something like “0013

RIOTTECHGPLPT 0

27SN……”

 

Note that all subordinate/attached boards in a probe have a default address of 0, and this ad-
dress must NEVER be changed!

 If you send the address change (aX0Ab!) command to an inter-

nally daisy chained board, this will render that board and all subsequent boards unresponsive 
and inoperative. 

Extended SDI-12 Command List 

Command 

Meaning 

Response 

aXSc!

 

aA ON<CR><LF> for c=A 
aOFF<CR><LF> for c=0 

Enable power to daisy chained 

board (GPLP-4, 5, 6 or 8) 

aXM!

 

aMode: n<CR><LF> 

read the current mode setting 

aXMn!

 

aMode: n<CR><LF> 

write the new mode setting to 

aXCn! 

aCoeff(n): cccccccc<CR><LF>  read the coefficient n setting 

Summary of Contents for GroPoint Profile 2625-N Series

Page 1: ...GroPoint Profile Multi Segment Soil Moisture Temperature Profiling Probe Models 2625 N T x 2625 N x and 3060 x OPERATION MANUAL 1 December 2020 V1 1 ...

Page 2: ...orks 8 Basic SDI 12 Command List 8 Understanding the Basic Commands 8 Query Address Command 8 Acknowledge Active Command a 9 Send Identification String Command aI 9 Change Address Command aAb 9 Start Measurement Command aM or aM1 or aM2 10 Start Concurrent Measurement Command aC 10 Send Data Command aD0 or aD 10 Extended SDI 12 Command List 11 Overview 11 Extended SDI 12 Command List 12 Extended C...

Page 3: ...on Process 23 Introduction 23 Overview 23 Equipment Required 24 Procedure 25 Entering Coefficients into the Probe 29 Appendix C Determining Volumetric Moisture Content Weight Method In Laboratory 31 Procedure Overview 31 Equipment Required 31 Soil Sampling Ring Requirements 31 Sampling Ring calculation 31 Sampling Method 31 Example Calculation 34 Appendix D Modbus Programming Manual 35 Modbus Comm...

Page 4: ...on the sensor takes measurements over multi ple soil layers with each measurement zone providing the average volumetric soil moisture con tent over a 15 cm 6 inch zone The probe is attached to a 3 meter 9 8 cable Soil tempera ture measurements are also available Technology TDT GroPoint sensors and probes use Time Domain Transmissometry TDT and patented tech nology as the basis for its measurement ...

Page 5: ...ts Reserved 2020 RIOT Technology Corp GroPoint Profile Model Variations The GroPoint Profile sensor can be ordered with and without temperature sensors The in formation in this manual covers material for sensors with temperature sensors If you have or dered sensors without temperature sensors the commands applicable to the temperature sen sor readings will be inactive Model numbers of sensors are ...

Page 6: ...rp 220 10114 McDonald Park Rd North Saanich V8L5X8 BC Canada 1 250 412 6642 www riotwireless com www gropoint com All Rights Reserved 2020 RIOT Technology Corp Probe Technology The drawing below shows the probe dimensions of the 2 8 segment probes Temperature sen sor locations provided in table below ...

Page 7: ... by an 8 3 ms mark space then the command char acters Note for a complete description of the SDI 12 communications protocol please refer to http www sdi 12 org specification php GroPoint Profile probes may be read with any compatible SDI 12 Modbus or RS485 logger communications interface or reader unit RIOT offer accessories for reading SDI 12 sensors the GroPoint GP DU SDI 12 Display Unit Part 26...

Page 8: ...e CR LF carriage return line feed sequence Basic SDI 12 Command List The GroPoint Lite Profiling Probes respond to the following basic SDI 12 commands In all cases a sensor address Default sensor address is 0 Command Meaning Response Address Query Device address default address is 0 a Acknowledge Device address default address is 0 aI Send Identification Identification string aAb Change Address Ch...

Page 9: ...r and firmware version number The command consists of the sensor s address the I character and the command termination character For example the response for a sensor with address 0 the default address is as follows 0I 013RIOTTECHGPLPTN027SN300123 CR LF This ID string identifies the supported SDI 12 compatibility level as 1 3 sensor vendor as RIOTTECH RIOT Technology Corp the sensor model as GPLPT...

Page 10: ...urement is complete 1M 10024 CR LF sensor 1 will be ready in 002 seconds with 4 measurements 1 CR LF sensor 1 sends this when the measurement is complete The actual measurement may take less than the expected time of 002 seconds The service re quest will be sent by the sensors as soon as the measurement is complete and data is ready Start Concurrent Measurement Command aC Use this command to start...

Page 11: ...7 a0022 3 5 10 20 30 40 50 60 70 75 GPLP 6 2 2 2 GPLPTM 10 7 3 M1 M2 a0027 a0023 3 5 10 20 30 40 50 60 70 80 90 GPLP 6 3 3 GPLPTN 11 7 4 M1 M2 a0027 a0024 3 5 10 20 30 40 50 55 65 75 85 90 GPLP 8 2 2 2 2 GPLPTM 13 7 6 M1 M2 a0027 a0026 3 5 10 20 30 40 50 60 70 80 90 100 110 120 GPLP 8 3 3 2 GPLPTN 14 7 7 M1 M2 a0027 a0027 3 5 10 20 30 40 50 55 65 75 85 95 100 110 120 All measurement values for a g...

Page 12: ...rn off power to daisy chained boards to en sure the sensor returns to low power state so if additional commands are to be sent af ter a measurement the aXSA command must be resent to turn power back on Commands to a daisy chained board are embedded in the following special extended command format aXncommand where n is the position in the daisy chain 1 is for the first attached board segments 3 and...

Page 13: ...special actions taken Mode 1 Enable application of third order polynomial to the measurement value Mode 1 allows the measured moisture value m to be recalculated by application of a third order polynomial equation to the original measured value m The new reported value m is given by the expression m A m3 B m2 C m D The coefficient A B C and D are viewed and modified using the aXCn Command see belo...

Page 14: ...al segment 1 C 2 coefficient B in 3rd order polynomial segment 1 C 3 coefficient C in 3rd order polynomial segment 1 C 4 coefficient D in 3rd order polynomial segment 1 C 5 segment 2 scaling factor C 6 coefficient A in 3rd order polynomial segment 2 C 7 coefficient B in 3rd order polynomial segment 2 C 8 coefficient C in 3rd order polynomial segment 2 C 9 coefficient D in 3rd order polynomial segm...

Page 15: ...ent 0 is the scaling factor for segment 1 coefficient 5 is the scaling factor for segment 2 etc Command Table Read Modify Third Order Polynomial Coefficient GPLP 3 Coefficient Commands Seg Coeff Read Write Default decimal Default hex 1 scale 0 aXC0 aXC0cccccccc 0 09765625 3DC80000 1 A 1 aXC1 aXC1cccccccc 0 00000000 1 B 2 aXC2 aXC2cccccccc 0 00000000 1 C 3 aXC3 aXC3cccccccc 1 3F800000 1 D 4 aXC4 aX...

Page 16: ...80000 4 A 6 aX1XC6 aX1XC6cccccccc 0 00000000 4 B 7 aX1XC7 aX1XC7cccccccc 0 00000000 4 C 8 aX1XC8 aX1XC8cccccccc 1 3F800000 4 D 9 aX1XC9 aX1XC9cccccccc 0 00000000 Command must be preceded by aXSA to enable power to second board GPLP 5 Coefficient Commands Seg Coeff Read Write Default decimal Default hex 1 scale 0 aXC0 aXC0cccccccc 0 09765625 3DC80000 1 A 1 aXC1 aXC1cccccccc 0 00000000 1 B 2 aXC2 aX...

Page 17: ...rite Default decimal Default hex 1 scale 0 aXC0 aXC0cccccccc 0 09765625 3DC80000 1 A 1 aXC1 aXC1cccccccc 0 00000000 1 B 2 aXC2 aXC2cccccccc 0 00000000 1 C 3 aXC3 aXC3cccccccc 1 3F800000 1 D 4 aXC4 aXC4cccccccc 0 00000000 2 scale 5 aXC5 aXC5cccccccc 0 09765625 3DC80000 2 A 6 aXC6 aXC6cccccccc 0 00000000 2 B 7 aXC7 aXC7cccccccc 0 00000000 2 C 8 aXC8 aXC8cccccccc 1 3F800000 2 D 9 aXC9 aXC9cccccccc 0 ...

Page 18: ...65625 3DC80000 6 A B aX1XCB aX1XCBcccccccc 0 00000000 6 B C aX1XCC aX1XCCcccccccc 0 00000000 6 C D aX1XCD aX1XCDcccccccc 1 3F800000 6 D E aX1XCE aX1XCEcccccccc 0 00000000 Command must be preceded by aXSA to enable power to second board Additional Product Information Specifications Moisture Measurement 0 to 100 volumetric water con tent Temperature 20 C to 70 C accuracy 0 5 C Output SDI 12 V1 3 all...

Page 19: ...rded installation example Press Ctrl and click simultaneously to see link directly to the online training video Videos GroPoint Soil Moisture Sensing Caution Wear Your Protective Equipment Care must be taken when using and carrying the slide hammer as the bottom part of the slide may drop down potentially causing injury Steel toed work shoes are recommended to prevent possible injury to toes and f...

Page 20: ...tion may place ex cessive force on the threads and damage them have 2 adjustable wrenches available one to hold the pilot rod a second to tighten the slide hammer shaft onto the pilot rod Drive the pilot rod only as far as needed for the length of probe being used A hole that is too short may cause damage to the probe during insertion A hole that is too long may allow water to collect in the void ...

Page 21: ...stable wrenches to make sure the threads are tight A loose connection can damage the threads as you are hammering 4 At the location where you want to install the probe use a repetitive up then down mo tion on the slide hammer to vertically drive the pilot rod into the soil Be sure to hold the slide hammer vertically without side to side movement Drive the pilot rod in until it reaches the tape mar...

Page 22: ...nough for the sensor probe and save the soil 2 Place the sensor probe vertically in the hole 3 While supporting the sensor at the top and bottom so that it does not move backfill the hole with the soil that was removed from the hole using the same soil at each depth as best as possible Be sure to keep the sensor vertical while backfilling the hole 4 Pack the soil around and into the sensor so that...

Page 23: ...has the default address 0 0XM0 You can also use the GPLP Reader program to disable the third order polynomial via the check box on the Coefficients dialog Overview Sensor readings are taken in a variety of soil moisture levels and are compared with manually determined volumetric moisture contents The first soil moisture level is the initial moisture of the dry soil after it has been allowed to air...

Page 24: ...ected chart the results and then apply a polynomial fit to the data points to establish the soil calibration coefficients Equipment Required Soil that is being calibrated initially dried to less than 5 should have a sufficient amount to fill the soil box Basic Equipment A soil container box Plastic Sheeting to cover soil to minimize loss of moisture due to evaporation and if necessary to line the ...

Page 25: ...hen handling soil Face mask dry soil is very dusty avoid inhaling dust particularly until the second or third moisture level Lab coat protect your clothes from becoming soiled Procedure 1 Initial Soil Preparation Soil is left out for two to three weeks in uncovered containers to allow it dry down to the ambi ent humidity Alternatively soil may be oven dried to reduce moisture content down to appro...

Page 26: ...water to add at each stage is determined based on soil volume mass Use the type of soil and the total volume of the soil to estimate the total amount of water to reach soil saturation For example if working with a sandy loam soil then soil saturation is reached at ap proximately 34 38 volumetric moisture content exact amount depends on precise soil tex ture If the volume of the soil is 25 liters t...

Page 27: ...atu rated when measured moisture level no longer increases 4 Data Analysis Required Software These instructions assume the use of Microsoft Excel Please refer to Excel s Help for assistance with using a spreadsheet and charting the data For other applications e g Open Office please refer to application program s help system Calculating Measurements Enter each moisture level s measurements into spr...

Page 28: ... from the Seg data column value measured by the sensor the Y data should be from the Reference Moisture column value determined manually Do a separate chart for each segment Select each chart then select the Chart Add Trendline menu option The type of trend line should be polynomial select either 2 or 3 for the order of the polynomial and for trend line options choose Display equation on chart and...

Page 29: ...his is done using the extended SDI 12 command aXCi where a sensor address default address is 0 and i is the coefficient to modify Please refer to the extended commands section for more details A USB to SD 12 interface product part 6300 is available that simpli fies the task of viewing and changing the probe s coefficient Contact RioT Technology for more information General Observations to Note Loa...

Page 30: ...pport gropoint com or visit www gropoint com support RIOT Technology Corp 220 10114 McDonald Park Rd North Saanich V8L5X8 BC Canada 1 250 412 6642 www riotwireless com www gropoint com All Rights Reserved 2020 RIOT Technology Corp ...

Page 31: ...eramic bowl Microwave oven Soil Sampling Ring Requirements The soil sampling ring should be a thin walled metal cylinder A section of metal pipe may be used provided the wall thickness is no more than 1 5 mm a wall that is too thick may cause soil compaction as the cylinder is pressed into the soil which could introduce errors in the measurement Sampling Ring calculation Calculate the volume of th...

Page 32: ...hour or more after adding water 2 Stir soil with trowel or fingers then tamp soil down to desired compaction level ideally this would be with the probe still in the soil just after the probe measurements are taken 3 Use the trowel to dig a small hole 4 Push the sampling ring into undisturbed soil on the side of the hole Try to ensure no additional soil compaction that is do not pack the cylinder m...

Page 33: ...ogy Corp 5 Remove the sampling ring from the soil by scraping the surrounding soil away use the tongue depressor until the ring is exposed 6 Cut away any excess soil from the open ends of the sampling ring and also ensure the that the outside of the sampling ring is free of soil 7 Empty the contents of the sampling ring into the ceramic bowl 8 Weigh the soil sample and cup together on the scale to...

Page 34: ...ight 10 Use this weight difference divided by the sample cylinder volume for example 33 5 ml to calculate the volumetric moisture content The difference in sample weight is due to the moisture that was boiled off from the sample Example Calculation Initial Weight 368 7 g Final Weight 362 8 g Difference 368 7 g 362 8 g 5 9 g 5 9 ml Volumetric Moisture Content 5 9 ml 33 5 ml 0 176 ml ml 17 6 Importa...

Page 35: ...For more information about Modbus RTU protocol please visit www modbus org Modbus Command Functions Supported Function Codes Commands The GPLP Modbus probe supports the following subset of Modbus commands Function Code Name Notes Broad cast 03 0x03 Read Holding Registers Maximum of 9 in one read No 04 0x04 Read Input Registers Moisture Values Temperature Sensor Values Maximum of 9 in one read No 0...

Page 36: ...rate this re sponse 01 81 01 CRCL CRCH which is interpreted as 01 Slave Address 81 Function Code Exception on command function 0x01 01 Exception Code Illegal Function CRCL CRCH CRC bytes Exception codes are 01 Illegal Function the command function is not supported 02 Illegal Data Address the register address does not exist 03 Illegal Data Value attempt to set an illegal data value for example ille...

Page 37: ...hen writing 8 bit values the upper byte should be set to 0 but is ignored in any event Byte order when reading and writing 8 bit values to and from the 16 bit registers is the same as for 16 bit values that is the high byte value of 0 first followed by the low byte Register 16 bit register data address n Bits 15 to 8 Bits 7 to 0 ex value 0 8 bit value IEEE 754 32 bit Floating Point Values Floating...

Page 38: ... 6 GPLP 8 30006 Segment 6 Moisture reading GPLP 6 GPLP 8 30007 Segment 7 Moisture reading GPLP 8 30008 Segment 8 Moisture reading GPLP 8 30009 to 30100 undefined reserved for future use 30101 Temperature Sensor 1 GPLP 2 GPLP 3 GPLP 4 GPLP 5 GPLP 6 GPLP 8 30102 Temperature Sensor 2 GPLP 2 GPLP 3 GPLP 4 GPLP 5 GPLP 6 GPLP 8 30103 Temperature Sensor 3 GPLP 2 GPLP 3 GPLP 4 GPLP 5 GPLP 6 GPLP 8 30104 T...

Page 39: ... response the sensor will only respond once the measurements are completed Holding Registers Read Function Code 03 Write Function Code 06 These are registers that can be read and written These registers contain scaling and polyno mial coefficients as well as operational settings communication settings sensor address etc Read response timeout is typically immediate Write response timeout is delayed...

Page 40: ...IEEE float 0 40057 40058 Segment 6 third order polynomial C 32 bit IEEE float 1 40059 40060 Segment 6 third order polynomial D 32 bit IEEE float 0 40066 40062 Segment 7 scale factor 32 bit IEEE float 0 09765625 40063 40064 Segment 7 third order polynomial A 32 bit IEEE float 0 40065 40066 Segment 7 third order polynomial B 32 bit IEEE float 0 40067 40068 Segment 7 third order polynomial C 32 bit I...

Page 41: ...fficient The default value of this coefficient is 100 0 1024 0 09765625 0x3DC80000 This gives a nominal output range of 0 to 100 although typically values over 50 are quite nonlinear This value should not be changed Changing the scaling factor will likely require recalibration of the sensor so it is advised to leave this factor unchanged and instead modify the third order polynomial coefficients s...

Page 42: ...eived Serial Parity Setting register 40204 decimal offset 0203 hexadecimal 0x00CB This register sets the serial parity setting It has a factory default value of 2 corresponding to Even parity Use the Write Single Register command to change this value to any of the follow ing valid values 0 None 1 Odd 2 Even The new parity setting does not take effect until the sensor is power cycled or if the rest...

Page 43: ...t com support RIOT Technology Corp 220 10114 McDonald Park Rd North Saanich V8L5X8 BC Canada 1 250 412 6642 www riotwireless com www gropoint com All Rights Reserved 2020 RIOT Technology Corp Appendix E Accessories Click here for full description of GroPoint Accessories ...

Page 44: ...N 61326 1 2013 Electrical equipment for measurement control and laboratory use EMC requirements EN 50581 2012 Technical documentation for the assessment of electrical and electronic products with respect to the restriction of hazardous substances Be advised that based on the information available to us from our raw material suppliers the products manufactured by us do not contain as intentional ad...

Page 45: ...the brand associated with RioT soil moisture and temperature monitoring solutions and technology We have the historical expertise forall GroPoint products in houseand available to assist former clients of E S I Environmental Sensors and new clients interestedinleveragingover25yearsofsoilmonitor ingexpertise across the science agricultural smart agriculture irrigation hydrological and indus trial s...

Reviews: