Daktronics AF-3020-7.6-R,A - Manual (Page 17)

To prepare for power and signal entrance:
1. Release the face panel latches using a tubular key (provided by Daktronics).
2. Open the face panel.
3. Clear the center punch area for drilling.
Punch or drill out the desired center punch. Be careful that none of the internal components are
damaged. Attach the conduit and route the power and signal cables. Refer to Drawing A-88427 and
A-140262 for an illustration of the power and signal termination panels.
3.3 Power
The body of this paragraph will give installation specific details for each manual receiving this
section. It will include system risers, shop drawings and assembly drawings. It will also include
voltage requirements if the manual is for a specific location.
Proper power installation is imperative for proper display operation. The following sub-sections give
details of display power installation. Qualified personnel must perform electrical installations.
Unqualified personnel should not attempt to install the electrical equipment. Serious danger to
equipment and personnel could occur if equipment is improperly installed.
G ounding r
t
Displays must be grounded according to the provisions outlined in Article 250 of the National
Electrical Code
® . Daktronics recommends a resistance to ground of 10 ohms or less. The
electrical contractor who is performing the electrical installation can perform verification of
ground resistance. Scoreboard Sales and Service personnel can also perform this service
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.
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. The support structure of the display cannot be used as an earth-ground electrode. The
support is generally embedded in concrete, and if in earth, the steel is either primed or it corrodes,
making it a poor ground.
Power Ins allation
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 12 for installation details. The
National Electrical Code requires the use of a lockable power disconnect within sight of or at
the display.
Electrical Installation 3-3