Daktronics AF-3400-12-RGB - Manual (Page 14)

The power J-box on the back of the display is provided with ¾” threaded holes for use with
¾” conduit. If necessary, knockout/drill holes are provided in the display cabinet itself when
not using the enclosure.
3.3 Power Requirements
Each display uses one 120 VAC or 120/240 VAC single phase power source. Proper power
installation is imperative for proper display operation. Refer to Drawing A-254277 for power
specifications for the specific display size.
Main Disconnect
The National Electrical Code requires the use of a lockable power disconnect near the
display. Provide a lockable disconnect switch (knife switch) at the display location so that all
power lines can be completely disconnected. Use a 3-conductor disconnect so that both hot
lines and the neutral can be disconnected. The main disconnect should be mounted at or near
the point of power supply connection to the display. A main disconnect is to be provided for
each supply circuit to the display.
The disconnecting means must be located in a direct line-of-sight from the display or outline
lighting that it controls. This requirement provides protection by enabling a worker to keep
the disconnecting means within view while working on the display.
Exception: Disconnecting means that are capable of being locked in the open position may be
located elsewhere.
Grounding
This sign is to be installed in accordance with the requirements of Article 600 of the National
Electrical Code and/or other applicable local codes. This includes proper grounding and
bonding of the sign.
For these displays, installation with ground and neutral conductors provided is used. The
power cable must contain an isolated earth-ground conductor. Refer to Figure 5 for the an
overview of proper grounding.
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.
The display system must be connected to earth-ground. Proper grounding is necessary for
reliable equipment operation. It also protects the equipment from damaging electrical
disturbances and lightning.
The display must be properly grounded, or the warranty will be void.
Electrical Installation 8