Power Supply; Additional Voltages; Power Distribution; Power Good - AGFA Avantra 36/44 Service Manual

Avantra 36/44 Service Manual
2.9

Power Supply

The power supply is a low voltage switching supply, with non-adjustable outputs.
A switch mounted to the side of the power supply configures the input voltages of
110 or 220 volts. The 300 watt power supply generates the following voltages:
+ 5.0 volts
+24.0 volts
+12.0 volts
-12.0 volts

2.9.1 Additional Voltages

Two other voltages necessary to the system are generated locally with converters
on the DEC PCB:
- 5.2 V
9.0 V
The -5.2 volts derives from -12.0 volts, which is used for the ECL logic on the DEC.
The +9.0 volts derives from the +12.0 volts and is used to supply power to the diag-
nostic modem.

2.9.2 Power Distribution

A discrete wiring harness provides power from the power supply to the DEC PCB.
The signal cabling supplies power for isolated boards within the system. This har-
ness will be included with the power supply as a complete field replaceable unit.

2.9.3 Power Good

The power supply generates a "power good" signal, which is used as a reset within
the system. This signal goes "true" when all supplies are within regulation specifi-
cation. The signal goes "false" at least 2 ms. prior to any of the supplies going out
of regulation. This gives the DEC and OCP enough time to save any non-volatile
parameters that may have changed since the last power-up cycle.
CAUTION:
not necessary to check or replace it. If the fuse should burn out,
consider the power supply as the cause.
2-14 Functional Analysis
20.0 amps
8.0 amps
1.0 amp
1.5 amps
An internal fuse is located in the power supply, but it is