Daktronics DF-1060 - Manual (Page 16)

2-4 Mechanical and Electrical
Specifications
The material for an earth-ground electrode differs from region to region and may
vary according to 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 it is in earth, the structural steel is usually primed or it corrodes,
making it a poor ground in either case.
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 circuit must contain an isolated earth-ground conductor. In
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 power disconnect within sight of or at the display.
Installation with Only a Neutral Conductor Provided. Installations where no
grounding conductor is provided 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, the following guidelines must be observed:
• 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.
2.3 Power and Signal Connection
Reference Drawings
Quick Install, DF-1060 Lottery Displays ...................... Drawing A-198033
Schematic; 16 Col Multipurpose LED Drvr.................. Drawing A-179599
16 Col. MASC Driver Specification.............................. Drawing A-184475
Route power and signal cables into the display from the side or rear. There are
7 /
8
"
knockouts for
1
/
2
" conduit fittings on the sides of all DataMaster cabinets and on the
back panels. All power and signal wiring terminates at the driver enclosure.
Refer to Drawing A-198033 for a complete review of power and signal connections
for DataMaster Rate displays. Drawing A-184475 illustrates and provides
connection specifications for the 16-column driver used in all DataMaster Lottery
displays. The schematic for the driver details both the wiring in the enclosure and
external connections to the display. Power and signal connections are illustrated in
Figure 4.