36 Troubleshooting
START
"OUTPUT HELD HIGH"
TURN OFF THE SUPPLY AND REMOVE THE
COVER AND RFI SHIELD. DISCONNECT LOAD.
TURN SUPPLY ON AND CHECK THE BIAS AND
REFERENCE VOLTAGES (TEST POINTS 9
THROUGH 22 . SEE TABLE 6-3.
NO
YES
ARE
VOLTAGES
OK?
DISABLE THE OV CIRCUIT BY LIFTING
A10R536. TURN ON SUPPLY AND PROGRAM
OUTPUT VOLTAGE AND CURRENT TO ZERO.
CHECK IF CV "OR" GATE DIODE
A10D652 IS CONDUCTING
A10D652
CONDUCTING?
NO
YES
CHECK VOLTAGE LEVEL AT FAST SENSE
DIFF AMP A10U608-7 49 .
DOES
TP 49
= -10V?
NO
YES
PROBABLE DEFECTIVE A6 BOARD
PROBABLE DEFECTIVE A10 BOARD
PROBABLE DEFECTIVE A10 BOARD
PROBABLE DEFECTIVE A10 BOARD
OR A8 FAST SENSE BOARD
Figure 3-6. Output Held High Troubleshooting)
Summary of Contents for 669 A Series
Page 2: ...Service Manual Keysight Series 669xA GPIB DC Power Supplies ...
Page 3: ......
Page 27: ......
Page 56: ...Troubleshooting 53 Figure 3 15 3 Inch Front Panel Frame Assembly ...
Page 57: ...54 Troubleshooting Figure 3 16 Assembly A10 Exploded View ...
Page 58: ...Troubleshooting 55 Figure 3 17 Assembly A10 Exploded View 6690A ...
Page 59: ...56 Troubleshooting Figure 3 18 Assembly A10 Exploded View 6691A 6692A ...
Page 60: ...Troubleshooting 57 Figure 3 19 Three Phase Line Choke Subchassis Wiring ...
Page 61: ...58 Troubleshooting Figure 3 20 24 Volt Fan Transformer ...
Page 77: ...74 Diagrams Figure 6 1 Test Point Waveforms for Table 6 3 sheet 2 of 2 ...
Page 79: ...Figure 6 3 A1 Front Panel Board Assembly Diagram ...
Page 81: ...Figure 6 5 A2 GPIB Board Component Location ...
Page 83: ...Figure 6 7 A3 FET Board Component and Test Point Location ...
Page 87: ...Figure 6 11 A4 AC Input Board Component and Test Point Location 12 9 10 11 ...
Page 89: ...Figure 6 13 A5 DC Rail Board Component and Test Point Location 13 14 ...
Page 91: ...Figure 6 15 A6 Bias Board Component and Test Point Location 15 16 17 18 19 19 20 22 ...
Page 94: ...Figure 6 17 Power Mesh Schematic Diagram All Models ...
Page 103: ......