HP 8550 Service Manual - Page 287
Power supply, logic system and sensors.
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Power supply Figure 173 is an outline of the power supply system in the ADF. The power supply is provided by the copy module with 24 V dc (24 VP, 24 VL). l 24 VP is mainly used for loads and is cut off when the ADF is opened or its upper cover is opened. The circuit breaker (CB1) operates to cut off the power to protect the circuit in response to overcurrent. l 24 VL is converted by the regulator into 5 V and is used by the logic system and sensors. l The fuse resistance (R26) melts in response to overcurrent in the circuit, thereby cutting off the power and protecting the circuit. Figure 173. Power supply EN ADF 285
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EN
ADF
285
Power supply
Figure 173 is an outline of the power supply system in the ADF.
The power supply is provided by the copy module with 24 V dc
(24 VP, 24 VL).
l
24 VP is mainly used for loads and is cut off when the ADF is
opened or its upper cover is opened. The circuit breaker (CB1)
operates to cut off the power to protect the circuit in response to
overcurrent.
l
24 VL is converted by the regulator into 5 V and is used by the
logic system and sensors.
l
The fuse resistance (R26) melts in response to overcurrent in the
circuit, thereby cutting off the power and protecting the circuit.
Figure 173.
Power supply