Troubleshooting 41
Note
Because test points on the FET board are not accessible when the board is installed, troubleshooting must
be performed with the board removed from the power supply (refer to the disassembly procedures at the
back of this chapter
If any power FET (Q201-204, Q301-304, Q211, Q311, Q222, Q322, Q233, Q333, Q244, Q344) is
defective, you must replace all eight with a matched set.
TURN OFF SUPPLY AND REMOVE
A3 FET BOARD WITH HEATSINK
MEASURE RESISTANCE BETWEEN
+RAIL AND -RAIL (E201 AND E301)
>=20 Mohm?
>15 Kohms?
CONTINUE WITH DYNAMIC
YES
YES
YES
NO
NO
NO
(SEE DISASSEMBLY PROCEDURES)
PROBABLE DEFECTIVE
A3 BOARD
MEASURE RESISTANCE BETWEEN
THE GATE OF EACH FET AND
COMMON (-RAIL)
MEASURE RESISTANCE ACROSS
CAPACITOR C201 AND C301.
approx.
150 ohms?
YES
NO
MEASURE RESISTANCE ACROSS
15V BIAS INPUT.
1k ohm forward?
490 ohm reverse?
TROUBLESHOOTING IN TABLE 6-3.
NOTE:
BECAUSE TEST POINTS ON THE A3 FET BOARD ARE NOT
ACCESSIBLE WHEN THE BOARD IS INSTALLED, TROUBLESHOOTING
MUST BE PERFORMED WITH THE BOARD REMOVED FROM THE SUPPLY.
ASSEMBLY ATTACHED.
PROBABLE DEFECTIVE
A3 BOARD
PROBABLE DEFECTIVE
A3 BOARD
PROBABLE DEFECTIVE
A3 BOARD
(E206 TO E207 AND E306 TO E307)
Figure 3-11. FET Troubleshooting Chart)
Содержание 669 A Series
Страница 2: ...Service Manual Keysight Series 669xA GPIB DC Power Supplies ...
Страница 3: ......
Страница 27: ......
Страница 56: ...Troubleshooting 53 Figure 3 15 3 Inch Front Panel Frame Assembly ...
Страница 57: ...54 Troubleshooting Figure 3 16 Assembly A10 Exploded View ...
Страница 58: ...Troubleshooting 55 Figure 3 17 Assembly A10 Exploded View 6690A ...
Страница 59: ...56 Troubleshooting Figure 3 18 Assembly A10 Exploded View 6691A 6692A ...
Страница 60: ...Troubleshooting 57 Figure 3 19 Three Phase Line Choke Subchassis Wiring ...
Страница 61: ...58 Troubleshooting Figure 3 20 24 Volt Fan Transformer ...
Страница 77: ...74 Diagrams Figure 6 1 Test Point Waveforms for Table 6 3 sheet 2 of 2 ...
Страница 79: ...Figure 6 3 A1 Front Panel Board Assembly Diagram ...
Страница 81: ...Figure 6 5 A2 GPIB Board Component Location ...
Страница 83: ...Figure 6 7 A3 FET Board Component and Test Point Location ...
Страница 87: ...Figure 6 11 A4 AC Input Board Component and Test Point Location 12 9 10 11 ...
Страница 89: ...Figure 6 13 A5 DC Rail Board Component and Test Point Location 13 14 ...
Страница 91: ...Figure 6 15 A6 Bias Board Component and Test Point Location 15 16 17 18 19 19 20 22 ...
Страница 94: ...Figure 6 17 Power Mesh Schematic Diagram All Models ...
Страница 103: ......