American Power Conversion MX28B4800 manual Battery Connections, Planning the Battery Installation

If the AC input power is provided from a three-phase distribution panel, the circuit breaker positions should be selected such that the load is balanced as much as possible.

WARNING: The MX28B DC power plant is supplied from a high voltage source. Keep the AC input enclosure in place when the system is operational or energized.

3.4. Battery Connections

WARNING: Hazardous energy levels are present on bare conductors in the - 48VDC distribution connection area of the plant. Accidental shorting of distribution conductors can cause arcing and high currents that can cause serious burns or other physical harm. It is recommended that:

c.Any jewelry, rings or watches be removed while working on this equipment.

d.Handles of all wrenches, screwdrivers, cutters and pliers are insulated.

Planning the Battery Installation

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

An external fuse or circuit breaker (various options are available from APC) is recommended in the negative line (located at the battery end) to protect the cables from the battery to the MX28B DC power plant. The power plant can monitor auxiliary contacts from this breaker.

MX28B1200/2400 MX28B1200/4800 –48 VDC User’s Manual Page 11