To ensure proper operation and to meet safety and electromagnetic interference (EMI) requirements,
you must connect an EX9251 switch to earth ground before you connect power to the switch. You must
use the protective earthing terminal on the rear panel of the switch chassis to connect the switch to
earth ground.
WARNING: The switch is installed in a restricted-access location. It has a separate
protective earthing terminal on the rear panel of the chassis that must be permanently
connected to earth ground to adequately ground the chassis and protect the operator
from electrical hazards.
CAUTION: Before switch installation begins, ensure that a licensed electrician has
attached an appropriate grounding lug to the grounding cable that you supply. Using a
grounding cable with an incorrectly attached lug can damage the switch.
Grounding Points Specifications for an EX9251 Switch
Two threaded holes are provided on the rear left side of the chassis for connecting the switch to earth
ground. The grounding points fit 10–32 screws and are spaced at 0.63 in. (16 mm) centers.
NOTE: Additional grounding is provided to an AC-powered switch when you plug its power
supplies into grounded AC power receptacles.
Grounding Cable Specifications for an EX9251 Switch
The grounding cable that you provide must meet the specifications in
.
Table 27: Grounding Cable Specifications
Cable Type
Quantity and Specification
Grounding
The grounding lug accommodates 14–10 AWG (2–5.3 mm²) stranded
wire. The grounding cable that you provide for the chassis must be the
same size or heavier than the input wire of each power supply.
Minimum recommendations are 14–10 AWG (2–5.3 mm²) stranded
wire, 60° C wire, or one that complies with the local code.
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