Preparing for Router Installation
Chassis Grounding
To meet safety andelectromagnetic interference (EMI) requirements and to
ensure proper operation, the router must be adequ ately grounded before power
is connected. A pair of threaded inserts (PEM nuts) are provided on the right
rear of the chassis for connectingthe router to earth ground.
CAUTION: Before router installationbegins, a licensed electrician must attach a
cable lug to the grounding and powercables that you supply. A cable with an
incorrectly attached lugcan damage the router (for example, by causing a short
circuit).
To groundthe router, connect a grounding cable to earth groundand then
attach it to the chassis grounding points. The grounding points are spac ed at
0.625-in. (15.86-mm) centers. The ac cessory box shipped with the router
includes the cable lug that attachesto the grounding cable (see Figure 28) and
the UNC 1/4–20 screws (American) used to secure the grounding cable to the
grounding points. (The cable lugshown in Figure 28 is also used for the DC power
cables.) Thegroundingcablemustbeabletohandleupto82A.
Figure 28: Power and Grounding Cable Lug
Crimp area
All measurements in inches
0.28
2 holes
2.25
0.25 0.37
0.63
g002137
0.55
End view
0.08
Thegroundingcablemustbe8-AWG(8.4m
2) wire, minimum, or
as permitted by the local code.
Power, Connection, and Cable Specifications
Tosupply power to the router,connect power cables to a separate, dedicatedpower
source for each powersupply and attach the cables to the terminal studs on the
circuit breaker box. Most site s distribute power through a main conduit that leads
to frame-mounted power distribution panels, one of which might be located at the
top of the rack that houses the router. A pair of cables (one input and one return)
connects each set of terminalstuds to the power distribution panel.
CAUTION: There is no standard color coding for DC power cables. The color coding
used by the external DC powersource at your site determines the color coding
for the leads on the powercables that attach to the terminal studs on the circuit
Power Guidelines, Requirements,and Specifications 67