Daktronics AB-1600-1.5,2.5 - Manual (Page 26)

Electrical Installation 3-6
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:
Installation with Ground and Neutral Conductors Provided
For this type of installation, 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. Refer to Figure 27 for a rough detail of how this
installation might look. The National Electrical Code requires the use of a lockable power
disconnect within sight of or at the display.
Installation with Only a Neutral Conductor Provided
Installations without a grounding conductor must comply with Article 250-32 of the
National Electrical Code. If the installation in question meets all of the requirements of
article 250-32, follow the guidelines listed below:
• = Connect the grounding electrode cable at the local disconnect, never at the display
entrance enclosure.
• = A disconnect that opens all of the ungrounded phase conductors should be used.
• = Bond the neutral and the ground conductors in the display power entrance enclosure.
Figure 27: Installation with Ground and Neutral Conductor Provided