System Overview The TorqueTrak 20K Torque Telemetry System utilizes proven digital RF technology to transmit a single data signal (most typically from a strain gage) a distance of 10 feet (3 meters) or more depending on the environment. Up to 16 systems can operate simultaneously on independent channels.
1.1 TX20K Transmitter High signal-to-noise ratio for excellent resolution Low temperature coefficient for accuracy from -40 to 85°C Wide power supply input range from 6 to 20VDC Power Standby mode to extend battery life Two on-board shunt calibration values ...
Configurable input for optional speed sensor. Simple Configuration and Monitor PC software included as well as serial protocol information for digital interface to data acquisition systems. Features and Controls The TT20K is a dynamic torque measurement system designed for temporary installations.
application. A higher RF power level will allow for more reliable transmissions over longer distances or in noisy RF environments. The lower RF power levels will increase battery life longevity. The RX20K always operates at maximum allowable RF power level since it is not battery operated.
2.1.2 LED Indicators Starting with the upper left LED and moving clockwise, the indicators are RNG, RXD Data, USB Data, and RPM. During power-up initialization or after a system reset, the normal LED pattern has both USB Data and RPM LEDs OFF while RNG and RXD Data LEDs alternate being ON.
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2.1.2.1 Range (RNG) LED The Range LED is ON solid green when torque values are being received from the TX20K and are within range. If no torque values are being received, the Range LED is OFF. If torque error value(s) are received, the Range LED flashes at a rate of 2Hz.
2.1.2.2 RF Receive Data (RXD) LED The green RXD Data LED is retriggered ON for 20msec when a byte is received by the RF transceiver of the RX20K. If the 20msec ON duration expires before another byte is received, the RXD Data LED switches OFF until another byte is received.
2.2.2 LED Indicator The TX20K has one green indicator LED that is ON solid when it is operating in any mode other than Standby with no problems detected. In Standby mode the LED is OFF to conserve battery power. 2.2.2.1 Input Signal Out of Range When the input (strain gage) signal is detected to be out of range, the indicator LED flashes five times per second (5Hz).
The TX20K has seven user selectable input range settings from ±0.2 to ±20mV/V. The table below shows just the positive side. The transmitted signal sample has a maximum range of ±20000. This gives the output resolutions listed below for each range. Table 3, Input Ranges Input Input...
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each block is transmitted, the TX20K switches its transceiver to receive configuration commands from the RX20K. If a command is received before the next block needs to be sent, it is executed. If no command is received, the next sample block is transmitted at the scheduled interval. The TX20K always operates in this mode when it powers up.
2.2.5.3 Standby Mode This is the TX20K low power, sleep mode. It is used to conserve battery power between test sessions. No torque or status data is transmitted while in Standby Mode. The TX20K wakes from this mode every 15 seconds to see if the RX20K is sending Wake commands.
2.2.7 Signal to Noise Ratio Below are the TX20K’s typical Signal to Noise Ratios at the different range settings and sample rates. Table 6, TX20K signal to noise ratios Input 50sps (dB) 500sps (dB) 5000sps (dB) Range mV/V 2.2.8 RF Power Level The TX20K RF transmission power level is user adjustable.
2.2.10 Power Consumption The following table shows typical power supply current draw for the stream mode. Table 7, TX20K current draw, stream mode, 250K baud, 5000 sps Power Power supply current draw (mA) at the four RF power Supply (Vdc) levels 12.0 20.0...
Product Safety WARNING! PERSONAL INJURY DO NOT USE this product as a safety or emergency stop device or in any application where failure of the product could result in personal injury. Failure to comply with these instructions could result in death or serious injury.
the field. The BS900 Bridge Simulator and 9V Battery Connector have been provided for this purpose. See section 4.2 Bench Testing for details. 4.1 Field Testing Although the settings of the TX20K can be changed during operation of the system, it is best to determine the appropriate Transmitter Gain setting for a given application prior to installation.
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Secure to shaft. NOTE: If testing will not begin for some time, put the TX20K in Standby mode to save battery life. The Status Indicator light will turn off. A fresh battery will last for several days in this mode. 4.
4.2 Bench Testing 1. Connect Receiver Antenna to Antenna connector on the rear panel of the RX20K Receiver. Position magnetic-mount antenna with element installed near the TX20K, typically within 10 feet (3 meters). 2. Use a USB A male to B male cable to connect the RX20K to a computer for power and communications.
5.2 RX20K to USB Host Block Messages Table 9 - RX20K to USB Host Block Message Format byte byte variable, all Description index variables start with USBmsg2host.name. hdr.stx header start char, always 0x55 hdr.len # of bytes following this byte in the USB msg to the host (always even and ≥...
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byte byte variable, all Description index variables start with USBmsg2host.name. hdr.RXstat (LB) low byte of the RX20K status word b0 - NoTxData, no data rcvd from TX b1 - TxDataErr, error in data rcvd from TX b2 - CmdAck, valid cmd rcvd from USB host b3 - CmdNak, invalid...
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byte byte variable, all Description index variables start with USBmsg2host.name. hdr.RFcomm RF data baud/sps; 0x77: 250K, 5000sps 0x74: 250K, 500sps (default) 0x71: 250K, 50sps hdr.RFchan RF data channel index (ch# - 1), values 0x00 thru 0x0F hdr.RxRFpwr RX RF xmit power setting, values 0x00 thru 0x0F hdr.RxRFlevData...
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byte byte variable, all Description index variables start with USBmsg2host.name. hdr.rpmRel (HB) high byte of block start to Speed input -edge time hdr.spdShift Timer #right bit shift for Speed and Sync values. The upper nibble is the #bit shift for Sync. The lower nibble is the #bit shift for Speed.
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byte byte variable, all Description index variables start with USBmsg2host.name. hdr.exp[0] Expansion board type: 0x7f = none b7 – update expansion board configuration, flag This flag is used internally and always displays as '0'. See separate expansion board parameter tables for details of hdr.exp[0] through hdr.exp[7]...
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byte byte variable, all Description index variables start with USBmsg2host.name. hdr.Debug1 (HB) high byte of Debug1 samp[0] (LB) sample 0 low byte samp[0] (HB) sample 0 high byte (signed 16 bit) samp[1] (LB) sample 1 low byte samp[1] (HB) sample 1 high byte hdr.len samp[n-1] (LB) sample n-1 low byte...
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byte byte variable, all Description index variables start with USBmsg2host.name. hdr.len TXstat.Shunt b0 is shunt1 status b1 is shunt2 status 0 = Off, 1 = On b7:b2 - unused hdr.len TXstat.RFpwr b3:b0 = Transmitter RF TX power level setting b7:b4 - unused hdr.len TXstat.Misc b0 –...
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Table 10: Analog Output Expansion Board hdr.exp[ ] parameters hdr.exp[] name description byte inside index program mEXtype b7 – update expansion board configuration flag. Always write to this index after all other necessary indexes have been written. When b7 of index 0 is written as a '1', it triggers the RX20K to process the data in the 8 expansion...
5.3 USB Host to RX20K Commands Table 11 - USB host to RX20K Command Format. Command Description byte0 byte1 byte2 byte3 chksum code Read checksums 0x40 chksum byte 1 – 0x00 Forces bootloader checksum to be output in block header bytes Debug0 and program checksum to be output in Debug1...
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Command Description byte0 byte1 byte2 byte3 chksum code Expansion board configuration 0x50 chksum byte 1 - Expansion board parameter index byte 2 - Expansion board parameter value byte 1 - Index [0] is always the Expansion board type with a byte 2 value: 0xff = no expansion board...
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Command Description byte0 byte1 byte2 byte3 chksum code Speed input configuration 0x60 0x00 chksum byte1 – Speed input configuration b7:b4 - #bits to right shift sync timer value. b3:b0 - #bits to right shift speed timer value. Speed timer measures the period between negative speed input edges.
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Command Description byte0 byte1 byte2 byte3 chksum code Receiver Input Source control 0x65 0x00 chksum byte 1 - Input source value (0 to 7) 0 - transmitter (default) 1 - forced output value = +1/4FS 2 - forced output value = +1/2FS 3 - forced output value = +FS...
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Command Description byte0 byte1 byte2 byte3 chksum code Receiver RF communications 0x6a chksum byte1 – Operational mode Block = 0, Stream = 1, Standby = 2 byte2 – Block and Standby Mode byte2 is same as System RF communications (both RX and TX) below (cmd code 0x9a) value baud...
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Command Description byte0 byte1 byte2 byte3 chksum code System control: 0x90 0x00 chksum byte1 - RFU byte2 1 = Reset TT20K Transmitter 2 = Reset TT20K System System RF channel control 0x92 0x00 chksum byte 1 – RF channel value to set (0 to 15) value = RF channel (1 to 16) - 1 This document is subject to change without prior notification.
Appendix A: System Specifications Description of system specifications. TX20K Transmitter Specifications Power input 6.0 ~ 20VDC Current draw See section 2.2.10 Antenna Internal Operating -40 to +85°C temperature range (Ultralife 9V lithium battery -40 to +60°C) Size 26w x 16h x 52 lg mm (1.03"w x 0.64"h x 2.03"lg) Weight G force 3000Gs...
Serial Output Digital See paragraph 5 above. communication protocol Speed sensor power 4.2V @ up to18mA. Current draw for the speed sensor adds to the system USB 5V current draw. Speed sensor signal 10K ohm pull-up to 3.3V. Maximum input freq 10KHz input Speed sensor Spectec 0158M-2-2-2-1-5.
Torque on Round Shafts Step 1: Calculate Full Scale Torque, T (ft-lb) The Full Scale Torque corresponds to a system output of 10 V. For a solid steel shaft, use the calculator on our website at www.binsfeld.com or use the simplified equation below: (1510.38 x 10 ft-lb/in ─────────────────...
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Transmitter constant = 2.5V const Full Scale Output of System = 10 volts Poisson’s Ratio (0.30 for steel) This document is subject to change without prior notification. Binsfeld Engineering Inc. | 231-334-4383 www.binsfeld.com 869610-9_A2 Pg. 39...
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For example, given a solid steel shaft with: (shaft Outer Diameter, measured) = 3.000 inches GF (Gage Factor from gage package) = 2.08 (TX10K Gain setting) = 4000 (1510.38 x 10 ft-lb/in )(3.000 in) = ────────────────────── = 4,901 ft-lb (2.08) (4000) so 10 V output from the RX20K indicates 4,901 ft-lb of torque or 490.1 ft-lb/volt.
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4,901 ft-lb ─────── = Z = 0.9802 5,000 ft-lb Next, multiply the Scale Factor times the Transmitter Gain setting to find the System Gain setting. 4000 x 0.9802 = 3920 Scroll to the Gain parameter screen on the RX20K and set the System Gain to 3920.
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Shunt Calibration The more common method is to perform a shunt calibration. This method takes into account deviations in the setup from the strain gage to the transmitter, but unlike a deadweight calibration, none of the deviations in the physical parameters. The easiest way to conduct a shunt calibration is by enabling one of the reference shunt resistors on-board the TX20K.
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ε ── (Z)(V ε Legend of Terms Voltage Output with Shunt Applied (V) ε Strain Simulated by Shunt (µe, GF = 2.0) ε Full Scale Strain (µe, GF = 2.0) Scale Factor (one if no scaling) Full Scale Voltage Output (V) (10V) In this example, with Reference 1 applied, the calibrated Voltage Output would be calculated as follows: 100 µe...
Appendix C: Strain Gage Installation View BEI’s online Strain Gage Installation Training videos at www.binsfeld.com/torquetrak/torquetrak-revolution/training-videos.html (Also refer to instruction bulletin B-127-12 provided with GAK-2-200 Strain Gage Application Kit from Vishay Measurements Group, Inc., Raleigh, NC, 919-365-3800, www.measurementsgroup.com.) PREPARING THE SURFACE 1.
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PREPARING THE GAGE FOR MOUNTING 5. Using tweezers, remove one gage from its package. Using the plastic gage box as a clean surface, place the gage on it, bonding side down. Take a 6” piece of PCT-2M Mylar Tape and place it on the gage and terminal, centered.
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when glue is applied. Very little catalyst is needed. Lift the brush cap out and wipe excess on lip of bottle. Use just enough catalyst to wet gage surface. Before proceeding, allow catalyst to dry at least one minute under normal ambient conditions of + 75F and 30-65% relative humidity.
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WIRING THE GAGE 13. Tin each solder pad with a solder dot. (It is helpful to polish the solder tabs, e.g. with a fiberglass scratch brush or mild abrasive, before soldering.) Trim and tin the ends of the 4-conductor ribbon wire.
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Figure 2, Strain gage wiring This document is subject to change without prior notification. Binsfeld Engineering Inc. | 231-334-4383 www.binsfeld.com 869610-9_A2 Pg. 48...
Warranty and Service Information Limited Warranty Binsfeld Engineering Inc. warrants that its products will be free from defective material and workmanship for a period of one year from the date of delivery to the original purchaser and that its products will conform to specifications and standards published by Binsfeld Engineering Inc.
FCC Rules Part 15: Computing Devices This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation.
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