Xerox Phaser 7300B, Service Manual

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3-72 Phaser 7300 Color Printer Service Manual
Verifying Power Supply Operation
Verifying the power supply involves four steps:
■
Measuring the input and output voltages.
■
Checking the safety interlocks.
■
Ensuring the +5 VDC loop is complete.
■
Testing for a shorted motor or defective wiring which would shut down the
power supply or damage the Engine Controller Board.
Measuring Power Supply Voltages
1.
AC Input: With the DMM set to measure AC voltages, measure for power being
supplied to the printer. It should measure between 110 to 127 VAC (110 VAC
nominal) or 220 to 240 VAC (220 VAC nominal).
2.
DC Output: With the DMM set to measure DC voltages, measure the voltages at
the POWER connector on the bottom of the Engine Controller Board for +5 VDC,
+12 VDC and +34 VDC, see the POWER Connector Pinout below.
POWER Connector Pinout
Pin Voltage/Signal Level Pin Voltage/Signal Level
1 Ground (0V) 14 +34 V
2 Ground (0V) 15 +12 V
3 Ground (0V) 16 Upper Thermistor
4 Ground (0V) 17 Side Thermistor
5 +5 V 18 Lower Thermistor
6 +5 V 19 Fuser Fuse
7 +5 V 20 Duplex Gate Solenoid
8 +5 V 21 Front Fan Signal
9 COM (0V) 22 Face Up Solenoid
10 COM (0V) 23 Power Signal
11 COM (0V) 24 Power Signal
12 +34 V 25 Power Signal
13 +34 V 26 Power Signal
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26 2
25 1
S7300-014