Full Scale Torque - Magtrol HD-106 User Manual

Magtrol Hysteresis Dynamometers
9. Select resistors until two adjacent resistance values, within 1% or 2% of each other, cause
the reading to swing through zero. Do not use any resistance below 10K.
10. Once the correct resistance value has been established, a high quality 50 ppm/°C, 1% or
better, precision resistor (RN60C or RN65C) must be obtained. Permanently solder it onto
the board in the R20 position.
11. The ZERO control potentiometer, which was previously set to a mechanical center, should
now trim out any remaining imbalance.
Note:
8.1.2.2 Erratic Torque Reading
If the torque reading is erratic, then the problem could be a defective load cell or electronic component
in the dynamometer or readout device. It will be necessary to establish specifically what is defective.
At this time contact Magtrol Technical Assistance.
8.1.3 f S
ull Cale
If the dynamometer cannot obtain full torque and will not support the beam and weight at full scale,
a resistance or current check may be used to help locate the problem.
8.1.3.1 Resistance Check
1. Disconnect the 2-pin connector and the dynamometer line cord.
2. Measure the resistance across the 2-pin male plug at the dynamometer.
3. Check the reading to the table below.
If something has caused the original balance to shift to such an
extent that the rear panel ZERO balancing control is out of range,
it is probable that more difficulties lie ahead. Whereas a new load
cell might offer the best solution, these instructions may get the
dynamometer operational.
T
orque
Dynamometer
Model
HD-106
HD-100
HD-400
HD-500
HD-510
HD-505
HD-515
HD-700
HD-710
HD-705
HD-715
HD-800
HD-810
HD-805
HD-815
HD-825
ED-715
ED-815
Resistance @ 20 °C
Ω
171
180
80
75
75
37.5
37.5
80
80
40
40
20
20
10
10
5
40
13
61
Chapter 8 – Troubleshooting