Ricoh FT5540 Service Manual page 99

The separation corona current is not always constant. It has two levels--a lead edge level and
the normal level. The normal separation corona current has an ac value of about 200
micro-amperes with little dc component. However, at the leading edge, the dc value is
reduced from about -2.5 micro-amperes to a dc component of about -8 micro-amperes. This
helps the leading edge of the paper separate from the drum. This is accomplished by the CPU
supplying a LOW signal at CN101-21B to the TC/SC power pack. (The above values for the
drum currents are theoretical calculations for total drum current.)
Normally, the lead edge separation corona current is applied to the first 10 millimeters of the
copy paper. However, you can select a margin of 7 or 13 millimeters using SP mode #37.
#37
0
1
2
Margin
10 mm
7 mm
13 mm
2-51
31 August 1989