Daktronics BA-1518-11, Инструкция по установке, эксплуатации и техническим характеристикам

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8.6 Power-On Self-Test
Reference Drawing:
Outdoor LED Power-Up Self Test ........................................................ Drawing A-133350
LED Bar Digit Power Up Self Test........................................................ Drawing A-133351
The scoreboard performs a self-test each time that power is turned on and the control console is
powered off or not attached to the scoreboard. If the control console is attached and powered on, the
self-test does not run, and data from the control console is displayed on the scoreboard after a brief
period.
The self-test runs in three cycles or phases. Each scoreboard self-test pattern will vary depending on
the scoreboard model, the number of drivers and types of digits.
Drawing A-133350 shows how the
test pattern displays in the digits with no protocol pins set on J26 of the LED drivers. Drawing A-
133351 shows a sample test pattern displayed on a scoreboard.
Cycle 1: Displays the protocol in the digits that are controlled by LED driver A1. P0 is
always displayed when P26 is not installed.
Cycle 2: Displays the driver number and address in the digits that are controlled by each
driver. A000 is always displayed when P25 is not installed.
Cycle 3: Displays a rotating patter in all digits. The pattern starts in row 1 and rotates
through row 8 (refer to
Drawing A-133350 ).
8.7 Lightning Protection
The transient voltage surge suppressor (TVSS), located in the load center, reduces the brief surge
induced into the power lines when lightning strikes in the vicinity of the scoreboard. A varistor in
the power lines to the driver logic also helps to protect this circuit by reducing such surges.
The use of a disconnect near the scoreboard to completely cut all current-carrying lines significantly
protects the circuits against lightning damage. The National Electrical Code also requires it. In order
for this system to provide protection, the power
must be disconnected when the scoreboard is not in
use. The control console should also be disconnected from power and from the signal junction box
when the system is not in use. The same surges that may damage the scoreboard’s driver can also
damage the console’s circuit.
8.8 Troubleshooting
Daktronics scoreboards require little maintenance. However, from time to time, a display may
malfunction, and certain display components will have to be repaired or replaced. The following
table provides a list of problems common to most LED displays and specifies corrective actions:
Symptom/Condition Possible Cause
Scoreboard will not light
§
Console not connected or poor connection.
§ No power to control console.
§
No power to the scoreboard.
(Continued on the next page)
Maintenance and Troubleshooting
8-5