HP 182C - Troubleshooting Tips; Power Supply

Model 182C
Table
8-3.
Low
Voltage Power
Supply Troubleshooting Tips
Symptom Suggested Checks
'Most common fault.
All supplies low or
high and unregulated.
Check
ac input line voltage and position of
rear-panel SELECTOR switch
(115 or 230V)
'Check
+
100V supply and A1A2VR2.
(-tlOOV
supply is used as reference for —100V,
-•-15V, —12.6V
supplies and
A1A2VR2 provides
reference voltage for -t-IOOV supply).
One
supply high and
unregulated with
high
ripple.
Check comparator and series regulator.
One supply low. Check for excessive
current
drain.
'Check comparator.
No
output from one
supply.
Check fuse.
Check regulator.
(Supplies are
current
limited. Fuse will
not open due to shorted load.)
Open line fuse. Check ac line voltage ar>d position of
rear-panel SELECTOR switch.
'Check rectifier
diodes.
Check filter capacitors.
Check power transformer.
Table
8-4.
Low Voltage Power
Supply
Measurement Conditions
1.
Setcontroisasfoiiows:
LiNE power ON.
Plug-ins not installed.
Line voltage
1 1 5
Vac.
2.
All dc voltages are referenced to ground.
3.
All
dc
voltages measured with HP Model 1414A Auto Voltmeter.
(100
MH input impedance).
4.
Voltages indicated on schematic remain approximately as
indicated when power supply is operated with HP Model
101 33A Service Extender.