Keithley 2182

Troubleshooting 4-11
Power supply checks
Power supply problems can be checked out using Table 4-3.
Table 4-3
Power supply checks
Step Item/component Required condition Remarks
1 Line fuse Check continuity. Remove to check.
2 Line voltage 120V/240V as required. Check power module position.
3 Line power Plugged into live
receptacle, power on.
Check for correct power-up
sequence.
4 U304, pin 2 +5V ±5% +5VD, referenced to TP301.
5 U305, pin 2 +37V ±5% +37V, referenced to TP301.
6 CR313 anode -6V ±20% -6VD, referenced to TP301.
7 Q304, pin 2 -5V, ±5% -5VD, referenced to TP301.
8 U302, pin 3 +15V ±5% +15V, referenced to TP303.
9 U303, pin 3 -15V ±5% -15V, referenced to TP303.
10 U301, pin 3 +5V ±5% +5V, referenced to TP303.
11 CR305 cathode +29V ±20% +29V, referenced to TP303.
12 CR309 anode -29V ±20% -29V, referenced to TP303.
13 CR310 V+, pin 1 +18V ±20% +18V, referenced to TP303.
14 CR310 V-, pin 2 -18V ±20% -18V, referenced to TP303.
15 CR306 anode -7V ±20% -7V, reference to TP303.
16 CR308 cathode +7V ±5% +7V, referenced to TP303.