Charge Corona Power Pack - Ricoh FT5540 Service Manual

31 August 1989

2.3 CHARGE CORONA POWER PACK

The circuit operation for the charge corona begins with the input of +5 volts (Vc) at CN2-3.
This voltage powers the LED of the photocoupler.
Additionally, 24 volts (Vp) enters the power pack at CN1-1. This power supply is used to
produce the high voltage corona. This voltage is interrupted if the front door safety switch
opens.
The charge corona turns on 260 milliseconds before the lead edge of the copy is detected by
the registration sensor. A LOW signal from the CPU (CN101-A20) is sent to the CC/B power
pack through the TC/SC power pack.
The OFF timing of the charge corona power pack varies according to the paper size being
used.
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