American Power Conversion MX28B2400, MX28B4800 manual Load Connections, Cable Size Considerations

3.8. Load Connections

Cable Size Considerations

The DC load cable(s) should be sized sufficiently large to limit the voltage drop from the MX28B DC power plant to the loads per system design requirements. The cable(s) must also carry the full load current during battery operation. During battery operation the voltage will be lower, therefore the current will typically be higher. If assistance is required to determine the necessary cables for the application, contact your sales representative or APC.

Circuit Breaker Connections (1 to 50 Amps)

Connections for 1 to 50 amp DC loads require standard two-hole lugs with holes for #10 screws (810-0032) on 5/8” centers and are located directly beside the corresponding circuit breaker. See for details.

Circuit Breaker Connections (60-100 Amps)

Circuit breakers rated for 60 to 100 amp DC are twice as wide as the smaller breakers and therefore require two positions and a circuit breaker adapter kit. The adaptor connects the two output lug positions to one lug. Adaptors are available with studs for #10-32 nuts on 5/8” centers, ¼-20 nuts on ¾” centers, or ¼-20 nuts on 1” centers. The adaptor is installed directly beside the two positions the circuit breaker is mounted on, using #10 screws provided in the kit. The lugs (not included with the kit) fasten on to the adaptor’s studs using nuts and washers provided in the kit. See for details.

Return Connections (1-100 Amps)

The load returns connect to the return buses located to the outside of the breaker connection points as seen in Error! Reference source not found.. Each return bus provides 28 sets of threaded #10-32 holes on 5/8” centers, fourteen sets of threaded ¼-20 holes on 5/8” centers and fourteen sets of threaded ¼-20 holes on 1” centers for connection of two-hole lugs on load return wires.

MX28B1200/2400 MX28B1200/4800 –48 VDC User’s Manual Page 22