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C
HAPTER
3. M
AINTENANCE
P
ROCEDURES
3-125
02.9631.0010
CONFIDENTIAL
15 Jan 98
3.3.24 Calibration
Procedures
3.3.24.1 Color and Gobo Wheel Sensor Calibration
The end of travel (EOT) sensors on the color and gobo wheels must be set
to the proper positions, with the filter wheels turning, to ensure correct
operation of the color and gobo changing mechanisms. The sensor, which
consists of a lamp and a phototransistor, provides a +15 VDC output when
reflected light is detected by the phototransistor and goes to 0 VDC when
light is not detected.
The sensor output will normally be +15 VDC, except when the black tape
on each wheel is in position to interrupt the sensor's light beam. When the
filter wheel spins continuously, the sensor provides a negative-going pulse
each time the sensor sees the black tape. The sensor is to be adjusted for
the widest pulse width. Ensure that the pulse drops to 3 VDC of
ground.
Parts:
1 EA
PROM,(PRGMD:27C256-2) VL2B HI TEST (87.7138.0001)
1 EA
PROM,(PRGMD:27C256-2) VL2B LOW TEST
(87.7138.0002)
1 EA
PROM, (PRGMD:27C256-2) VL2C HI TEST (87.7149.0001)
1 EA
PROM, (PRGMD:27C256-2) VL2C LO TEST (87.7149.0002)
Tools:
Screwdriver, Phillips #1
Screwdriver, Phillips #2
Wrench, open end, 1/4 inch
Oscilloscope with 10X probe
Lamp run cheater cable
To calibrate color or gobo wheel sensor:
Step 1.
Remove power to luminaire.
Step 2.
Open electronics chassis.
Step 3.
Remove lamp control board from card cage. Refer to Lamp
Control Board Removal and Replacement paragraph.
Step 4.
Remove EPROMs from lamp control board and install either
VL2B or VL2C luminaire test PROMs. Make sure that HI and
LOW PROMs are installed in correct positions.
Step 5.
Re-install lamp control board in luminaire.
Step 6.
Close, but do not fully secure, chassis lid.