Daktronics CH-836H - Manual (Page 19)

Section 3 : Maintenance & Troubleshooting
Maintenance & Troubleshooting
3-1
IMPORTANT NOTES:
1. Disconnect power before any repair or maintenance work is done on the
display!
2. Any access to internal display electronics must be made by qualified
service personnel.
3. Disconnect power when the display is not in use.
3.1 Lamp Replacement
Reference Drawing: Digit Service .................................................. Drawing A-27674
The primary service required by the CH-836H display is to replace burn-out lamps. Refer to
Drawing A-27674 for an illustration of lamp changing. Replacement lamps are 120V, 25W
frosted, medium base, available at your local store or directly from Daktronics, part number
DS-1029. Some displays may be equipped with 120V, 30W reflector type 30R20 lamps,
Daktronics part number DS-1126.
Do not use lamps larger than those originally installed in the display. Using higher powered
lamps will likely cause fuse failures in the display and could exceed the current levels that the
display's circuits can safely handle.
3.2 Lamp
Driver
Reference Drawings: Lamp Driver, 16 Col., w/ Fan....................... Drawing A-37070
Component Locations, CH-836H ................ Drawing A-47112
In the display, the task of switching lamps on and off is performed by the lamp driver.
Drawing A-47112 in Section 2 shows the location of the lamp driver in the display.
Drawing A-37070 is an illustration of the lamp driver and the fuses located in it.
The lamp driver has 21 connectors providing power and signal inputs and outputs to digits.
The functions of these connectors are as follows:
Connector Number Function
1-16 Outputs to digits
17 Signal Input
18 Power input for outputs 1-8 (120 V)
19 Power input for driver logic and fan (120V)
20 Power input for outputs 9-16 (120V)
24 Dim option selector
In Drawing A-47112, the numbers on the digits refer to the lamp driver output connector
wired to each digit.
3.3 Digit
Segmentation