C3KX-PWR-440WDC Cisco Catalyst 3K-X 440W DC Power Supply

The only DC supply for the Catalyst 3750-X and 3560-X families, also listed as PWR-C1-440WDC, and the only module in the group that is NEBS-compliant. It has two input feeds, A and B, taking -36 to -72 VDC. Domestic wiring runs -36 VDC minimum, -48 VDC nominal and -72 VDC maximum; the international range uses -60 VDC as nominal. Input current is 16 to 8 A, and the output is -56 V at 7.86 A, 440 W at most.

The module weighs 3.5 lb (1.6 kg), the heaviest of the group, and measures 1.38 x 10.22 x 3.25 in (3.5 x 26 x 8.3 cm) before the extraction handle, which adds 1.55 in (3.9 cm).

Wiring rules for the terminal block are specific. Use 14-AWG copper, 90 C wire with fork-type terminals and a UL-listed lug, match polarity, and torque the terminal screws to 11 lbf-in. The ground wire is 12 AWG or 8 AWG. Protect the circuit with a device rated no higher than 20 A and provide a readily accessible two-pole disconnect. The grounding design is DC-isolated. Connect ground first and disconnect it last, lock the breakers off while wiring, and put the terminal safety cover back when terminals are idle. The DC OK and PS OK LEDs show green on a healthy supply. The module can be paired with a second DC module or with an AC module in the other slot. The spare is ordered as C3KX-PWR-440WDC=.

The 715W AC power supply is the sibling for the same bays. Further modules are available from Cisco modules.