Dc Power Supply Troubleshooting; Lvps Overcurrent Protection Circuit; Lvps Overvoltage Protection Circuit; Lvps - Xerox Phaser 6128MFP Service Manual

General Troubleshooting

DC Power Supply Troubleshooting

LVPS Overcurrent Protection Circuit

LVPS Overvoltage Protection Circuit

LVPS

4-64
This circuit stops all outputs if any of the Low Voltage Power Supply voltages 3.3
VDC, 5 VDC, or 24 VDC are shorted. The circuit is reset when the short is removed,
the power is turned Off, and then On again.
This circuit stops all outputs if the power supply voltage 3.3 VDC, 5 VDC, or 24 VDC
exceeds the specified voltage respectively. The operating point is 32 VDC or less
for 24 VDC, 7 VDC or less for 5 VDC, or 4.4 VDC for 3.3 VDC.
Troubleshooting Reference Table
Applicable Parts
LVPS, PL10.6.16
MCU Board, PL10.7.7
Troubleshooting Procedure Table
Step Actions and Questions
1 Check the AC power supply (page 4-73).
Does the problem persist?
2 Turn the Power Switch Off.
Is the Fuse on the LVPS open?
3
1. Disconnect J501 and J502 from the
LVPS.
2. Turn the Power Switch On.
3. Measure the DC voltages between
these pins on the LVPS:
P501-1 <=> P501-2 = +5 V
P501-3 <=> P501-4 = +3.3 V
P502-1 <=> P502-2 = +24 V
Are all of the voltages present?
Wiring and Plug/Jack Map References
"LVPS" on page 10-14
Yes
Go to step 2. Complete.
Replace the
LVPS
(page 8-47).
Go to step 4. Replace the
Phaser 6128MFP Service Manual
No
Go to step 3.
LVPS
(page 8-47).