User's Guide

This document is subject to change without prior notification.
Binsfeld Engineering Inc. | 231-334-4383 www.binsfeld.com 869610-9_A2 Pg. 37
Serial Output Digital
communication
protocol
See paragraph 5 above.
Speed sensor power
4.2V @ up to18mA. Current draw for the speed sensor
adds to the system USB 5V current draw.
Speed sensor signal
input
10K ohm pull-up to 3.3V. Maximum input freq 10KHz
Speed sensor
example
Spectec 0158M-2-2-2-1-5. There are many variations.
www.spectecsensors.com
Analog output board
power
Powered by the RX20K main board from USB 5V.
Adds approximately 70mA plus maximum output load
current.
Analog output ranges
±3, ±5, ±10, 0 to 5, 0 to 10V
Analog output
impedance
325 ohms
Analog output offset
adjustment range
Half of full scale output.
Analog output scale
adjustment range
8 bit fixed point value with 2 bit integer word length.
0.015625 to 3.984375
Appendix B: Calibration Calculations
The equations in this Appendix define the relationship between the input
signal to the TX20K Transmitter (typically from a strain gage) and the
Full Scale output voltage of the TorqueTrak 20K System. The
calculations are based on parameters of the device being measured (e.g.
shaft diameter), sensor parameters (e.g. gage factor) and Transmitter
Gain setting.
Section B1 is specific to torque measurements on round shafts (full
bridge, 4 active arms).
Section B2 applies to axial strain (tension/compression) measurements
on round shafts (full bridge, 2.6 active arms).
Section B3 is for use with a single grid (1/4 bridge).
1 µe is distortion of the shaft surface 1 x 10
-6
in/in. For more technical
information regarding the relationship between shear strain and torque,
see the excellent technical article TN-512 published by Vishay.