JVC 250 service manual Arc Lamp - Main Functions, Arc Lamp - Inputs, Arc Lamp - Operation

Chapter 4---Optical

4.1 Arc Lamp

The Arc Lamp is the beginning of the high intensity Light Path. It is located inside a housing on the right side of the Optical Support Assembly (see Figure 4-5).

Arc Lamp - Main Functions:

The Arc Lamp is a single component composed of a Xenon gas bulb at the center of a compound elliptical reflector. It supplies the high intensity white light used by the projector to put a very bright image on the screen. The expected 50% life (half of initial light output) of an Arc Lamp is approximately 1000 hours.

Arc Lamp - Inputs

!32 kV pulse to light the Arc Lamp Power Supply

!2 kW constant power during normal operation

Arc Lamp - Operation

The Arc Lamp Power Supply and the Igniter Assembly work together to produce a 32 kV pulse that ignites the Arc Lamp. After the Arc Lamp lights, the voltage from the Arc Lamp Power Supply drops to a constant 25-31 volts at 70-85 amps. It will stay at this level during normal Arc Lamp operation.

Arc Lamp - Service Adjustments

When a new Arc Lamp is installed, it will need to be aligned using the Arc Lamp adjustment fixture located inside the Arc Lamp housing (see Figure 4-2).

Arc Lamp Adjustment

Tools Needed

Large Flatblade screwdriver

4-mm Hex-head wrench

Equipment Needed

Minolta Illumination Meter T-1 or equivalent

To align the Arc Lamp:

1.Remove the front cover (see Section 6.1).

2.Loosen the spider lock down bolt (see Figure 4-4).

3.Power the projector ON and let it run for 15 minutes to stabilize.

4.Verify that the "Shutters on Hide" box is checked in the System-

Preferences menu, then use the RGB key and the HIDE key to hide Red and Blue. This prevents light coming from the Red and Blue ILA® s.

5.Open the fan door of the Arc Lamp Enclosure housing using the large Flatblade screwdriver to rotate the retaining screws 90° This gains access to the three Arc Lamp alignment screws. The Arc Lamp fan disconnects when this door is opened.

4-2 Model 250 Service Manual