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V
ARI
*L
ITE®
-
VL2B
AND
VL2C
S
POT
L
UMINAIRE
S
ERVICE
M
ANUAL
CONFIDENTIAL
02.9631.0010
15 Jan 98
Step 14.
Loosen sensor.
a. For color wheels, loosen sensor vertical positioning screw
holding sensor to bracket.
b. For gobo wheel, loosen nut that holds sensor to mounting
bracket.
Step 15.
Move sensor toward or away from wheel until widest possible
pulse width is obtained. See Figure 3-47 for view of
acceptable sensor pulse waveforms.
+15.0 V
0.0 V
IDEAL
+15.0 V
0.0 V
NOT ACCEPTABLE
Figure 3-47. Sensor Pulse Waveforms
a. Verify that pulse drops to +3 VDC or lower.
b. For gobo wheel sensor, sensor must remain fairly
perpendicular to gobo wheel or light will not bounce back
to phototransistor at all.
c. Adjust oscilloscope HOLDOFF knob (only on Tektronix
model 2225 oscilloscope) to stabilize waveform if waveform
is jumping around on screen.
Step 16.
Secure sensor in calibrated position.
Step 17.
Disconnect lamp run cheater cable from AC outlet and then
disconnect cable from luminaire.
Step 18.
Disconnect oscilloscope from luminaire.
Step 1.
Remove lamp control board test EPROMs, re-install system
EPROMs in lamp control board, and secure chassis lid with six
10-32x3/8"PPB screws.
Step 20.
Secure head covers to rails with eight 6-32x5/16"PFB and 12,
6-32x5/16"PPB screws.