TM 5-6115-593-12
TO 35C2-3-463-1
Table 5-6. Automatic Control Module Troubleshooting (Organizational Level)-Continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
WARNING
Death or injury may result if proper care is not taken
while working with the various voltages in and
around the generator set.
NOTE
The frequency of normal power is observable at the
associated switchgear control.
Step 1. If frequency is over required rating and NORMAL POWER AVAILABLE indicator lamp is lit, inspect (using a
multimeter set to measure AC) for 120 V AC across Overfrequency Device 81N-0 relay 7-5 contacts (figure
2-19).
If 120V AC is present, refer testing and replacement of 81N-0 relay to next higher level of maintenance.
If 120V AC is absent, refer testing and replacement of TD relay to next higher level of maintenance.
Step 2. If frequency is under required rating and NORMAL POWER AVAILABLE indicator lamp is lit, inspect (using a
multimeter set to measure AC) for 120V AC across Underfrequency Device 81N-U relay 6-5 contacts (figure
2-19).
If 120V AC is present, refer testing and replacement of 81N-U relay to next higher level of maintenance.
If 120V AC is absent, refer testing and replacement of TD relay to next higher level of maintenance.
Step 3. If NORMAL POWER AVAILABLE indicator lamp is not lit, refer testing and replacement of Run Relay (RR)
to next higher level of maintenance.
2.
GENERATOR SET DOES NOT START WHEN NORMAL POWER VOLTAGE GOES OUT OF TOLERANCE.
NOTE
The voltage level of normal power is observable at the
associated switchgear control.
5-18
