Panasonic UF-580 Service Manual page 212

Fuser Lamp Drive Circuit
The Fuser Lamp is powered by 100 VAC (200 VAC). It is driven by the LVPS and controlled by the nSSR
signal from the SC PC Board. When the CN103, Pin11 (nSSR) on the LVPS goes LOW, the Fuser Lamp
turns ON. This lights up the PC102 LED and activates the TRC100 photo-triac, and VAC 115 VAC is sent
to the Fuser Lamp. The time at which TRC100 is actually activated depends on the 100 VAC (200 VAC)
sine wave. When the cross-voltage for Pin 6 and Pin 4 of PC102 is other than 0 Volts (sine wave
exceeds 0 volts), PC102 inhibits the activation of the triac and turns ON the Fuser Lamp.
R127
Fuser Lamp Drive Circuit Diagram
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