Hughes JVC 200, Service Manual

Page: 83 / 140

Chapter 3 Service Adjustments
3.2 Arc Lamp Current Setting
The Arc Lamp current must be set whenever an Arc Lamp or Arc
Lamp Power Supply is replaced. Routinely recheck current about
every 500 hours of operation. This procedure is performed using
two DVMs, for convenience, but can be performed with one DVM
by moving the leads back and forth between the two test points
mentioned and changing the scale ranges on the DVM.
To perform the Arc Lamp Current Setting:
1. Verify that power is off to the projector, or turn power off with
the remote (it is not necessary for the circuit breaker to be off).
2. Place a DVM (set to read up to 200VDC) across the Arc Lamp
DC INPUT
±
terminals, J74, ( Figure 3-3 ).
3. Turn projector power on.
Figure 3-3. Arc Lamp Power Supply connections.
4. Place another DVM, set to read at least 200 millivolts dc,
across the test points inside the small rectangular aperture,
near the upper left of the Arc Lamp Power Supply cover (see
Figure 3-4). NOTE: This test point reads millivolts across a
shunt that has been selected so that a 1 millivolt reading on the
DVM is equal to 1 amp of Arc Lamp current.
3-4 Model 200 Service Manual