3.6. DC Power Output Over-Current Protection
DC Circuit Breakers
A standard 24-position plug-in circuit breaker tier provides +24 Vdc distribution. Various circuit breaker sizes from 1 to 100 amps are available, with 60-100 amp breakers requiring two positions and a circuit breaker adapter kit. The breaker tier is connected at its center to the +24 Vdc bus, and each side has a current capacity of 300A. It is therefore necessary to balance the load on the power plant to avoid overloading the output bus. Also when planning the output installation, take into consideration the configuration of the plant and the number of rectifiers installed.
Any combination of up to 24 single (1-50 Amp) or up to 12 double (60-100 Amp) breakers may be installed. Figure 3.6-1shows the power plant’s distribution section with the front cover removed.
Figure 3.6-1 DC Distribution (Front Cover Removed)
Plug-in circuit breakers rated at 60A or more require two mounting positions and require a circuit breaker adapter, which is included in the circuit breaker kit. Adaptors are available with studs for #10-32 nuts on 5/8” centers, #10-32 nuts on ¾” centers, or ¼-20 nuts on 1” centers. The circuit breaker kit includes all necessary mounting hardware. Available plug-in circuit breakers and circuit breaker kits are shown in Figure 3.6-2.
MX28B400 +24 VDC User’s Manual | Page 10 |