Lucent Technologies Lineage
®
2000 400A, 60Hz Ferroresonant Rectifier J85503C-3
Issue 10 July 2000
Testing 6 - 17
Isolated Current
Measuring (VI)
Test
This procedure checks the isolated current measuring circuit (voltage
proportional to current adjustment) on the CM2 control board. The
procedure is required for plants using Galaxy controllers or Lineage
®
2000 MCS controllers and when the output current reading on the
rectifier does not agree to within
± 2.5 percent of the rectifier output current reading on the controller.
This procedure must be performed while connected to the controller and
a battery.
Refer to Figure 6-3 for components on the 208F control board. Plant
control cable connector J5A MUST be connected to P5A on CM4 for
this procedure.
1. Connect a DMM, set on the dc millivolt scale, across the rectifier
shunt. See Figure 5-3.
2. Adjust the rectifier to deliver approximately 200A, 50% of its
rated current capacity.
3. Observe the DMM and record the rectifier's shunt voltage. The
shunt is rated
500A/50mV = 10A/mV
which means that each millivolt of voltage drop across the shunt
indicates 10A of output current.
4. Convert the DMM's shunt voltage reading to amperes. For
example, if the DMM reads 40mV, then
40mV X 10A/mV = 400A
of output current. As this calculation indicates, the rectifier is
operating at full load, and the rectifier shunt voltage is 40mV at
full load.
5. Compare the amperes calculated in Step 4 with the rectifier drain
indication on the MCS controller.
6. If the rectifier drain indication is between 0 and 2% higher than
the amperes calculated in Step 4, and indicated on the MCS
controller, this procedure is completed.
7. If the rectifier drain indication is not as indicated in Step 6, adjust
potentiometer R35 on CM2 control board to obtain a rectifier
drain reading on the MCS controller that is between 0 and 2%
higher than the amperes calculated in Step 4.