APC MX28B-2400 User Manual

Page of 54
Revision B 
MX28B-1200   PRODUCT MANUAL 
MX28B-1200/2400 
27 
 
Figure 5-9  Plug-in Circuit Breaker Insertion 
 
5.8.2.2  Circuit Breaker Load Connections 
Connections for the -48V dc loads are located directly to the side of the corresponding breaker.   
A typical load connection would utilize a #6 AWG wire with a two-hole lug on 5/8-inch centers, 
attached with standard #10-32 mounting screws.  
The load return cables for each circuit breaker section connect to a return bus directly opposite 
the circuit breakers.  These return buses contain patterns for 28 two-hole #10-32 lugs on 5/8-
inch centers, and 14 two-hole ¼”-20 lugs on a double-pattern of either 5/8-inch or 1-inch 
centers. 
5.8.2.3  Power Distribution Fuse Load Connections 
Connection for the –48V dc loads are made to L-shaped 
landing pads connected to the distribution side of the 
fuse.  All the fuses within a given box frame have a 
common bus connection to –48V dc. Load side 
connections utilize a double-hole lug on 1 ¾ -inch 
centers and return connections are made to the common 
return bus bar at the top of the cabinet using 1-inch or 1 
¾ -inch lugs (Figure 5-10). 
 
 
 
 
Fuse Connections 
Figure 5-10  Fuse Bay Connections