Daktronics Galaxy AF-3200 34 mm User Manual
Page 14
Installation with Ground and Neutral Conductors Provided
For these displays, installation with ground and neutral conductors provided is used.
The power cable must contain an isolated earth-ground conductor. The display
must be properly grounded, or the warranty will be void.
Under this circumstance, do not connect neutral to ground at the disconnect or at the
display. This would violate electrical codes and void the warranty. Use a disconnect
so that all hot lines and neutral can be disconnected. The National Electrical Code
requires the use of a lockable disconnect within sight of or at the display.
In addition to the service ground, the display system must be connected to earth-
ground by means of ground rod or similar method. Refer to Figure 7. Proper
grounding is necessary for reliable equipment operation. It also protects the
equipment from damaging electrical disturbances and lightning.
Figure 7: Correct Grounding
Important points about grounding:
• Follow local and national codes: The material of an earth-ground electrode
differs from region to region and from conditions present at the site. Consult
the National Electrical Code and any local electrical codes that may apply.
• Support structure cannot be used as an earth-ground electrode: The support is
generally embedded in concrete. If in earth, the steel is either primed or it
corrodes, making it a poor ground.
• One grounding electrode for each display face: The grounding electrode is
typically one grounding rod for each display face. Other grounding electrodes
as described in Article 250 of the National Electric Code may be used.
• Resistance to ground 10 ohms or less: This is required by Daktronics for
proper display performance. If the resistance to ground is higher than 10 ohms,
it will be necessary to install additional grounding electrodes to reduce the
Power Installation
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