Cisco 2691 Series, Быстрый старт

Страница: 14 / 28

14
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 mm
2
) wire is required for DC input and
safety ground wire.
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).
Table 2 DC Wiring Requirements for Cisco 2691 Routers
Installed Power Supply DC Input
DC Input
Wire Size
1
1. See the note above this table for National Electric Code wire size requirements.
Safety Ground
Wire Size Overcurrent
Protection
Nominal 24/48 VDC
2
2. The input voltage tolerance limits for nominal 24/48 V power supplies are 18 and 72 VDC.
24 - 36 V, 8 A, positive or negative,
single or dual sources AWG 18
(1.0 mm
2
)
AWG 14
(2.0 mm
2
)
15 A maximum
36 - 60 V, 4 A, positive or negative,
single or dual sources AWG 18
(1.0 mm
2
)
AWG 14
(2.0 mm
2
))
15 A maximum