Daktronics FB-2700 Series, Руководство по установке, Страница: 21 / 60

Electrical Installation
17
Grounding
All components of a display system – including but not limited to displays, control
equipment, and connected peripheral equipment – must be electrically grounded.
Only qualified individuals may perform electrical work, including verification of ground
resistance. Daktronics is not responsible for improper grounding or damage incurred as a
result of improper grounding.
Grounding methods must meet the provisions of all applicable local and national codes.
Inspect and verify all grounding methods meet the provisions of all applicable local and
national codes.
Proper grounding is necessary for reliable equipment operation and general electrical
safety. Failure to properly ground the display system may void the warranty, disrupt
operation, damage equipment, and cause bodily harm or death.
There are two types of 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 subsections:
Installation with Ground and Neutral Conductors Provided
For this type of installation, the power circuit must contain an isolated earth-ground
conductor. In this circumstance, do not connect neutral to ground at the disconnect or
at the display as this would violate electrical codes and void the warranty.
Use a disconnect so that all ungrounded lines can be disconnected. The local and
national electrical codes may require using a lockable power disconnect at or within
sight of the display.
Installation with Only a Neutral Conductor Provided
Installations where no grounding conductor is provided must comply with local and
national electrical codes. If the installation meets all requirements, observe the following
guidelines:
• Connect the grounding electrode cable at the local disconnect, never at the display
driver/power enclosure.
• Use a disconnect that opens all of the ungrounded phase conductors.
Lightning Protection
The use of a disconnect near the display location to completely cut all current-carrying
lines significantly protects the circuits against lightning damage. Local and national
electrical codes may also require it. In order for this system to provide protection, the
power must be disconnected when the display is not in use.
The control console also should be disconnected from power and from the signal
junction box when the system is not in use. The same surges that may damage the
display components can also damage the console’s circuitry.