Daktronics Galaxy Series, Руководство пользователя

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Figure 19: Display Grounding
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. Daktronics requires that the resistance to ground be 10 ohms or less. If the
resistance to ground in higher than 10 ohms it will be necessary to install additional
grounding electrodes to reduce the resistance. The grounding electrode should be
installed within 25 feet of the base of the display. The grounding electrode must be
connected to the ground terminal in the display panel board.
Power Installation
There are two considerations for power installation: installation with ground and
neutral conductors provided and installation with only a neutral conductor provided.
These two power installations differ slightly, as described in the following
paragraphs:
Electrical Installation
3-7
r Installation with Ground and Neutral Conducto s Provided
For this type of installation, refer to
Figure 20
. The power cable must contain an
isolated earth-ground conductor. 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 power
disconnect within sight of or at the sign.
Figure 20: Installation with Ground and Neutral Conductor Provided