Lamp Voltage; Lamp Power Path - Accuprint AP42CL 8000 Service Manual

Lamp Voltage (Terminals 2 & 3)
Model
AL84 w/L1280
AL84 w/L1281
AL84 w/L1282
AL94 w/L1280
AL94 w/L1281
AL94 w/L1282
94MS42 Rev. B1 S/W Ver 2.06
• The internal interlock is a loop that travels through the light head, passing
through the glass switch and two thermostats. This interlock is in series
with the control circuit of the large relays in the power supply. When the
interlock is opened, the relays will open and cut the power to the lamp
terminals. The PC board senses the drop in voltage and closes the shutter.
• The first place to check is the glass switch. The switch lever is located
near the edge of the glass on the end of the lamp where the cable enters.
By releasing the glass, the lever can be seen. If the lever can slip past the
glass, it should be bent slightly toward the reflector. If the switch is closed,
the loop can be traced. First measure the voltage between lamp wires (#4
AC Common) and wire (#10 Interlock). The presence of voltage between
these terminals indicates an open loop. This loop travels to the lamp
head on wire (#10), then to the glass switch, the far end thermostat, the
near end thermostat and terminates on wire (#4). The thermostats are
mounted in the air tubes leading to the lamp. There are no splices in the
air tubes.

Lamp Voltage

The lamp voltage measurement can provide useful information for lamp
striking, lamp output, and level switching information. The meter used
to measure can cause different results. We use traditional needle
movement meters in our factory, due to the trigger pulses on the lamp
before striking. The waveforms are not sinusoidal, so different meters
may produce different results. Here is a chart with typical measurements:
Idle Low Med.
360-380 360-380 380-410 415-445
400-430 400-430 425-500
400-430 400-430 425-500
360-380 360-380 380-410 415-445
400-430 400-430 425-500
400-430 400-430 425-500

Lamp Power Path

The basic path that the power to the lamp takes is almost identical for all
units. The basic path is incoming line, main power relay, ballasts,
capacitors, trigger board, and then the lamp. See the point to point wiring
diagrams for each light source in Section 16.
Lamp Fan Voltage (Terminals 4 & 5)
High Trig. Idle/Low
500+ 75-95
460-530 500+ 75-95
460-530 500+ 75-95
500+ 70-90
460-530 500+ 65-90
460-530 500+ 65-90
Med. High Trig.
90-120 115-125 115-125
90-120 115-125 115-125
90-120 115-125 115-125
90-120 115-125 115-125
90-120 115-125 115-125
90-120 115-125 115-125
13-5