GE Bently Nevada 86517 Operation Manual page 23

1. Connect the Power Supply to the -24Vdc and COM terminals on the
interface module as shown and adjust the voltage to -24 Vdc. Connect the
multimeter to the +ACCEL terminal. Connect the 0.01 uF capacitor and function
generator as shown. The input should connect to pin C and leave pins A and B
unconnected. Connect the interface module case to common through the CASE
SHIELD terminal. Make sure the interface module case is isolated.
2. Adjust the function generator to a null output level and measure the
acceleration signal with the multimeter. If the reading is more than a few
millivolts rms then the test setup is probably injecting power line noise into the
charge amplifier. You need to lower the noise level before continuing. Try
reducing lead lengths and changing lead routing.
3. Adjust the function generator to output a 0.3535 Vrms sine wave at 100 Hz
for a transducer sensitivity of 50 pC/g, or 0.707 Vrms for a transducer sensitivity
of 100 pC/g.
4. Measure the acceleration output with the multimeter. If the output reads
0.3535 ±7.0 mVrms go to step 8.
If the output does not read 0.3535 Vrms ±7.0 mVrms continue with step 5
Section 4 - MAINTENANCE
19