Cisco Systems 2691 quick start DC Wiring Requirements, Statement

Caution If you connect dual DC power sources, both sources must be the same polarity. Do not connect a –DC with a +DC source to a Cisco 2691 router. Opposite-polarity sources damage the power supply.

DC Wiring Requirements

A Cisco 2691 router with a DC-input power supply requires copper wire for the power connections. Table 2 summarizes the wiring requirements.

You can connect a single DC power source to either the A input or the B input. If there are dual power sources, connect one source to the A input and one source to the B input; both sources must be the same polarity and voltage.

Note For installations compliant with the National Electric Code, AWG 14 (2.0 mm2) wire is required for DC input and safety ground wire.

Table 2	DC Wiring Requirements for Cisco 2691 Routers
			DC Input	Safety Ground	Overcurrent
Installed Power Supply		DC Input	Wire Size1	Wire Size	Protection
Nominal 24/48 VDC2		24 - 36 V, 8 A, positive or negative,	AWG 18	AWG 14	15 A maximum
		single or dual sources	(1.0 mm2)	(2.0 mm2)
		36 - 60 V, 4 A, positive or negative,	AWG 18	AWG 14	15 A maximum
		single or dual sources	(1.0 mm2)	(2.0 mm2))

1.See the note above this table for National Electric Code wire size requirements.

2.The input voltage tolerance limits for nominal 24/48 V power supplies are 18 and 72 VDC.

Wiring Procedure for DC Input

To connect the router to a DC power source, perform the following steps:

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 the 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 Strip the wires to the appropriate length for the terminals. The strip length is 3/16 in. to 1/4 in. (5 mm to 7 mm). Step 3 Remove the plastic covers from the terminal block. Save them for reinstallation after you finish wiring.

Note Do not remove the colored screw at either end of the terminal block. Those are the terminal mounting screws.

Step 4 Connect the wires to the terminal block, starting with the safety ground wire. Insert each wire into the appropriate terminal as shown in Figure 8. To avoid interference with the on/off switch, insert the wires from below. Tighten the terminal screws to 8.0 ± 0.5 in-lb (0.9 ± 0.05 N-m).

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