5-46 Accessory Troubleshooting
TP-5672 11/95
Is there rated line-to-line voltage
between terminals TB-AC1-EA and
TB-AC1-EC of the power supply board?
Is there rated line-to-line voltage
between terminals 36 and 46 of the
source selector switch?
Is the source selector switch in the
EMERG. EA-EC position?
Is there rated line-to-line voltage
between terminals 31 and 41 of the
source selector switch?
Is there rated line-to-line voltage at the
primary winding of the transformer
between the source selector switch and
the voltmeter?
Is there 120 vac at the secondaries of
the transformer (line-to-line voltage
must be at rated voltage)?
Is there 120 vac
?
20% between the
two terminals of the voltmeter?
Remove the resistor from the circuit and
measure its resistance. Is the
resistance 2500 ohms
?
10%?
Is the fuse between the transformer and
the voltmeter blown?
Refer to Power to the
System Troubleshooting.
Replace the leads from
terminals TB-AC1-EA and
TB-AC1-EC of the power
supply board to the
source selector switch.
Move the source selector
switch to the EMERG.
EA-EC position.
Replace the source
selector switch.
Replace the leads from
the source selector
switch to the transformer.
Replace the transformer.
Replace the voltmeter.
Replace the resistor.
Replace the fuse
between the transformer
and the voltmeter.
Replace the leads
from the transformer
to the voltmeter.
No
Yes
No
No
No
No
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
Yes
Figure 5-52. Troubleshooting— Option DD-18-J, Voltmeter does not read EA-EC voltage
