American Power Conversion VS 50 - Manual (Page 15)

Magnum VS –48 Vdc User Manual Page 15
2.7. Load Protection Installation
Circuit Breaker Installation
Standard circuit breaker output distribution modules are available with two 30-A breakers or one 60-A breaker.
Output distribution modules are installed at the factory and are typically not field replaceable units. Contact APC if
the output configuration is not suitable for your needs. Other breaker sizes are not readily available.
GMT Fuse Installation
The standard GMT output distribution module includes eight (8) fuse positions and is installed on the left side of the
Magnum VS shelf. The GMT fuse holders are located on the front panel of the unit. Insert the fuses into the
holder; observing the tripped indicator is correctly oriented. Use the chart shown in Figure 2.7-1 to help determine
what size fuses will carry the desired current. When using several of the larger GMT fuses in one shelf, better heat
dissipation will be achieved if the fuses are spaced out evenly within the output panel. The following GMT-type
fuses are provided by APC with the DCM00K03SGMT or DCM00K06SGMT Magnum VS systems: 1A, 3A, 5A,
7.5A, and 10A.
AMBIENT TEMPERATURE
20 ° C 50 ° C 60 ° C
7.5 A 5 A 4.5 A 4 A
10 A 7 A 6 A 5 A
FUSE SIZE
15 A 10 A 9 A 8 A
Figure 2.7-1 GMT Fuse Temperature De-rating Chart
2.8. Load Connections
Cable Size Considerations
The DC load cable(s) should be sized to limit the voltage drop from the 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 and for constant power loads, the current will typically be higher. If assistance is
required to determine the necessary cables for the application, contact your sales representative or APC.