C
HAPTER
3. M
AINTENANCE
P
ROCEDURES
3-39
02.9631.0010
CONFIDENTIAL
15 Jan 98
3.2.2.8
Edge Control Not Working Properly
On VL2B luminaires a common failure is the lens barrel getting jammed in
a extended position. This sometimes happens when the lens is left fully
extended when packed into a road case. The lens bearing tube is vibrated
and unseats itself during transport.
This simple problem can be avoided if the lens is retracted prior to power
down of luminaire. This problem is corrected on the VL2C luminaire
BFB. A retaining ring was added that prevents the bearing from jamming.
Step 1.
Open electronics chassis to gain access to mother board.
Step 2.
At mother board, ensure good yoke cable connection.
Step 3.
Remove head covers and inspect lens for smooth operation.
a. If no movement is detected or is intermittent, replace BFB
bulkhead with good spare and retest. Refer to
Brightness/Focus Bulkhead Replacement paragraph.
b. If fault is corrected then problem is in BFB bulkhead. If
problem persists then problem is with circuit.
Step 4.
Remove head assembly covers to gain access to YTB.
Step 5.
At YTB, ensure good yoke cable and linear actuator wire
connections.
Step 6.
At electronics chassis, replace CIB with known good board.
a. If new CIB solves problem U7 on faulty CIB and retest . If
problem not corrected then return bad CIB.
b. If replacement does not solve problem, re-install removed
control interface board and continue with next step.
Step 7.
At electronics chassis, replace LVS. Refer to Low Voltage
Supply Replacement paragraph.
Step 8.
At actuator motor, inspect for hot motor. Excessive heat could
indicate bad motor. Refer to Brightness/Focus Bulkhead
Replacement paragraph.
Step 9.
If symptoms persist, replace yoke cable. Refer to Yoke Cable
Assembly Removal and Replacement paragraph.