HP 3100, 3150 manual Power system on ECU, AC power distribution, DC power distribution

Power system (on ECU)

The AC, DC, and high-voltage power supply circuits are all contained within the ECU.

AC power distribution

The AC power circuitry supplies AC voltage whenever the power cord is connected to the AC power source. AC voltage is distributed to the DC power supply circuitry and to the AC driver circuitry, which controls AC voltage to the fusing assembly's heating element.

DC power distribution

The DC power distribution circuitry, located on the ECU, distributes +5 V DC and +12 V DC as follows:

Table 11. DC power distribution

+5 V DC:	Formatter
	Photosensors
	DC Controller Circuitry
	Laser/Beam Detect Circuitry
+12 V DC:	Motor
	Scanner Motor
	Solenoid
+12VA DC:	High Voltage Power Supply

Overcurrent/overvoltage

There are two overvoltage devices in this printer:

● Fuse F101 provides overcurrent protection for the fixing system circuitry. To check or replace the fuse requires the removal of the ECU. Fuse 102 (found only on 110V units) provides overcurrent protection to the printer DC power supply circuitry.

● In addition, the +12V DC and +5V DC power circuitry contains an overcurrent protection circuit which automatically shuts off the output voltage when an overcurrent condition occurs due to a short or abnormal voltage on the load side.

70 Functional overview EN