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C-4
Catalyst 3750 Switch Hardware Installation Guide
OL-6336-07
Appendix C Connecting to DC Power
Connecting to DC Power
Wiring the DC-Input Power Source
Warning
Before performing any of the following procedures, ensure that power is removed from the DC circuit.
Statement 1003
Warning
Only trained and qualified personnel should be allowed to install, replace, or service this equipment.
Statement 1030
Caution You must connect the Catalyst 3750G-12S-SD switch only to a DC-input power source that has an input
supply voltage from –36 to –72 VDC. If the supply voltage is not in this range, the switch might not
operate properly or might be damaged.
Caution The switch must be installed with 5 A-branch-circuit protection.
Note This installation must comply with all applicable codes.
To wire the switch to a DC-input power source, follow these steps:
Step 1 Apply tape to the circuit-breaker switch handle, and move the circuit-breaker handle to the off position.
Step 2 Locate and remove the terminal block plug (see Figure C-4).
Figure C-4 Terminal Block Plug
60530