Cisco 3640 Quick Start Manual page 19

DC Wiring Requirements
Cisco 3620 and Cisco 3640 routers with a DC-input power supply require copper wire for the power connections.
For Cisco 3640 routers, DC power connections require crimp-type ring terminals or spade terminals with upturned lugs.
Table 2 DC Wiring Requirements for Cisco 3620 and Cisco 3640 Routers
DC Power Source DC Input
–48 to –60 VDC
Nominal 48 VDC
1. The input voltage tolerance limits for nominal 48 V power supplies are 38 and 72 VDC.
Wiring Procedure for DC Input
To connect the router to a DC power source, perform this procedure.
Step 1 Remove power from the DC circuit. To ensure that power is removed from the DC circuit, locate the circuit breaker
for the DC circuit, switch the circuit breaker to the OFF position, and tape circuit-breaker switch in the OFF position.
Warning Before performing any of the following procedures, ensure that power is removed from the DC circuit.
Statement 1003
Tip Secure all power cabling when installing this unit to avoid disturbing field-wiring connections.
Step 2 For Cisco 3620 routers, strip the wires to the appropriate length for the terminal block on the power supply.
For Cisco 3640 routers, crimp appropriate ring terminals or spade terminals to the DC power input wires. Strip the
wires to the appropriate length for the terminals used. The following warning applies to Cisco 3640 routers:
Warning When stranded wiring is required, use approved wiring terminations, such as closed-loop or spade-type terminals
with upturned lugs. These terminations should be the appropriate size for the wires and should clamp both the
insulation and conductor. Statement 1002
Step 3 Connect the DC power input wires to the terminal block as shown in Figure 18 or Figure 19.
Warning The illustration shows the DC power supply terminal block. Wire the DC power supply as illustrated. The proper
wiring sequence is ground to ground, positive to positive, and negative to negative. The ground wire should
always be connected first and disconnected last. Statement 239
Warning An exposed wire lead from a DC-input power source can conduct harmful levels of electricity. Be sure that no
exposed portion of the DC-input power source wire extends from the terminal block plug. Statement 122
Caution The terminal arrangement on your router may not be identical to the arrangement shown in Figure 18 or Figure 19.
You must connect the positive, negative, and ground wires according to the labels on the terminals.
Caution Do not overtorque the terminal block captive thumbscrew or terminal block contact screws. The recommended
torque is 8.2
DC Input Wire Size
1
, 4A AWG 14 (2.0 mm
0.4 in-lb (0.9 0.05 N-m).
Safety Ground Wire Size
2
) AWG 14 (2.0 mm
Overcurrent Protection
2
) 15A, maximum
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