JVC 250 - Projector Power Supply Units

Chapter 3---Electrical
Model 250 Service Manual 3-3
3.3 Power Supplies
All Series 200 projectors including the Model 250 have three power supplies.
These include:
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Low Voltage Power Supply
!
Arc Lamp Power Supply
!
High Voltage Power Supply
There is a fourth power supply, the Laser Power Supply, but that power supply is
used only for the Igniter Assembly during Arc Lamp lighting.
Low Voltage Power Supply (LVPS)
LVPS - Main Functions:
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Provides all the low voltages needed by the projector.
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Provides standby power (+5.1V) when the projector is OFF but the AC
Circuit Breaker is in the ON position.
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Provides power (+24 V) for all cooling fans.
LVPS - Inputs
:
The Low Voltage Power Supply receives AC input power directly from the AC
Line Filter. The input range is from 220 VAC to 240 VAC, at 50/60 Hz.
/LV_ENA - from the System Controller PCB. This signal enables the LVPS when
the System Controller receives a Power On command.
/FAN_ENA - from the System Controller PCB. This signal enables the +24v
standby voltage for the projector fans.
/COVER_ON - signal enables the non-standby outputs.
/ = Active low
LVPS - Outputs:
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+ 5.1VDC Main
!
+ 5.1VDC Stdby
!
+ 6.2VDC
!
± 15VDC
!
+ 24VDC
!
+ 80VDC
/LV_OK - this diagnostic signal tells the System Controller PCB the status of the
non-standby supply (all the outputs are working or not working).