Keithley 2500 - Power Supply Checks

Model 2500 Service Manual Troubleshooting 4-11
Power supply checks
Power supply problems can be checked out using Table 4-2. See “Principles of operation”
for circuit theory on the power supply.
Table 4-2
Power supply checks
Step Item/component* Required condition Remarks
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
Line fuse
Line power
+5VDA TP
+5VA TP
-15VA TP
+5VA TP
-5VA TP
+110VA TP
-110VA TP
+5VDB TP
+5VB TP
-15VB TP
+5VB TP
-5VB TP
+110VB TP
-110VB TP
Check continuity.
Plugged into live receptacle, power on.
+5V, ±5%
+15V ±5%
-15V, ±5%
+5V, ±5%
-5V, ±5%
+110V, ±20%
-110V, ±20%
+5V, ±5%
+15V ±5%
-15V, ±5%
+5V, ±5%
-5V, ±5%
+110V, ±20%
-110V, ±20%
Remove to check.
Check for correct power-up sequence.
Referenced to GND DA TP.
Referenced to GND A TP.
Referenced to GND A TP.
Referenced to GND A TP.
Referenced to GND A TP.
Referenced to GND A TP.
Referenced to GND A TP.
Referenced to GND DB TP.
Referenced to GND B TP.
Referenced to GND B TP.
Referenced to GND B TP
Referenced to GND B TP.
Referenced to GND B TP.
Referenced to GND B TP.
*Test points (TP) are marked on circuit board.