Specifications

2-2
2.2 Wiring (continued)
2.2.1.2 The control cabinet ground must be a single point termination
and be at a resistance of less than 1 ohm with relation to true
earth. All grounds within the control cabinet must be connected
to the single point ground termination.
2.2.1.3 High voltage wiring (> 50 V) must be run in separate conduit
from low voltage (<50 V) or signal wiring. If run parallel to each
other, high voltage wiring should be separated from low voltage
and signal wiring by 12 inches or as much as physically possi-
ble. If they must cross each other, they should cross perpendic-
ularly.
2.2.1.4 Shielded cable should be used for signal wiring to prevent
electrical noise contamination. The shield should be terminated
at the ZVD only. (NOTE: Terminating the shield at both ends
causes ground loops and defeats the purpose of using shielded
cable).
2.2.1.5 Low voltage wiring making long runs outside a control cabinet
should use shielded cable also. Shield termination should be at
the end of the cable connected to the equipment requiring the
most noise protection. (NOTE: In some cases, this may be the
PC or PLC, rather than the ZVD).
2.2.2 NEMA 12
Wiring connections for the NEMA 12 enclosure are shown on page E-3.
NOTE: The NEMA 12 enclosure is not provided with any pre-punched conduit holes.
The customer is required to punch holes in the enclosure to facilitate field wire
entrance. The customer should ensure that the entrance holes and conduit conform to
local wiring codes.