Daktronics AF-3090-89-R,A - Manual (Page 20)

Electrical Installation
3-5
3. Route power to the display through a fused disconnect switch capable of opening all ungrounded
power conductors. Locate this disconnect within the line of sight of any personnel performing
maintenance on the display. If the disconnect is located out of sight of the display, it must be
capable of being locked in the open position.
4. Power conductors from the disconnect to the display must route through conduit in agreement
with local codes.
5. You may also route the signal cable from the control computer to the sign at this time. Run the
power and signal cables in a separate conduit.
3.6 Power
Reference Drawings:
AF-3090 Controller Assembly, RS232/422 .............................................Drawing A-158254
Power Specs, AF-3090, Amber ...............................................................Drawing A-158396
AF-3090 Controller Assembly Modem ....................................................Drawing A-162098
AF-3090 Controller Assembly Fiber ........................................................Drawing A-162099
Power Specs, AF-3090, Red LEDs .........................................................Drawing A-162439
Schematic, AF-3090-8-32x***-24, Mono ................................................ Drawing B-161855
Refer to Drawings A-158396 and A-162439 for voltage and current requirements for your sign size.
Each uses a 120/240VAC single -phase or 120/208 three-phase power source.
Do not connect the signs to any voltage other than that listed on the Daktronics product label.
Proper power installation is imperative for proper display operation. The following sub-sections give
details of display power installation. Electrical installations must be performed by qualified personnel.
Unqualified personnel should not attempt to install the electrical equipment. Serious danger to
equipment and personnel could occur if equipment is improperly installed.
Grounding
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.
Verification of ground resistance can be performed by the electrical contractor who is performing
the electrical installation. Daktronics 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.
A minimum of one grounding electrode must be installed 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. Daktronics recommends that
the resistance to ground be 10 ohms or less. If the resistance to ground is 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 panelboard.
This grounding electrode must be installed in addition to the equipment grounding conductor that
should be part of the power installation. The material of an earth-ground electrode differs from
region to region and from conditions present at the site. 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. The grounding