Electrical And Signal Ground - Emerson Daniel Danalyzer 1000 Hardware Reference Manual

MODEL 1000
3.1.4

Electrical and Signal Ground

Follow these general precautions for grounding electrical and signal lines:
(1) For shielded signal conducting cables, shield-drain wires must not be more than two AWG
sizes smaller than the conductors for the cable. Shielding is grounded at only one end.
(2) Metal conduit used for process signal wiring must be grounded at conduit support points
(intermittent grounding of conduit helps prevent induction of magnetic loops between the
conduit and cable shielding).
(3) A clamp type ground lug (color green) is located on the inside bottom front of the GC
Controller's case. Chassis ground conductors (color code green) inside the Controller's
enclosure should be stranded, insulated copper wire.
conductors should all be connected to the clamp type ground lug.
(4) A clamp type ground lug is located on the outside of the GC Controller's case at the rear of
the lower right (facing the operator panel) casting rib. This ground point should be
connected to a copper ground rod as described next.
(5) A single-point ground (the outside case ground lug) must be connected to a copper-clad, 10-
foot long, 0.75" diameter steel rod, which is buried, full-length, vertically into the soil as
close to the equipment as is practical. (Grounding rod furnished by others.)
(6) Resistance between the copper-clad steel ground rod and the earth ground must not exceed
25 Ohms.
INSTALLATION AND SETUP
Observe Precautions and Warnings
1
Plan Site Location
2
Obtain Supplies and Tools
3
Install Analyzer Wiring
4
These device chassis ground
SEP 2005
3-9