Emerson 15-90KVA Manuel D’Utilisation

Page de 132
Electrical Connections—UPS
26
3.2.7
Accessory Fuses and Backfeed Breaker Wiring
Two fuse blocks provide power for the backfeed breakers (standard) and the BDSi (optional). See 
Figure 11 for fuse holder locations.
The backfeed breaker fuse block provides 120V nominal provided from the UPS output (L-N) and the 
fuse is rated for 8 amps. Figure 12 shows the backfeed breaker wiring.
The BDSi fuse block provides 208V nominal from the UPS output (L-L) and the fuse is rated at 8A. 
The BDSi power wiring is shown in Figures 23 an46.
Figure 11 Accessory fuses
Figure 12 Dual input backfeed breaker wiring when bypass distribution cabinet not used
NOTE
Shunt trips are required in upstream breakers to allow backfeed protection to function 
properly.
BDSi Fuse 
Block 
(optional)
Backfeed 
Breaker 
Fuse Block
UAM04030
Rev. 1
Auxiliary contacts not needed
for backfeed breaker operation
Upstream Bypass Breaker
To UPS
Bypass Input
Upstream Rectifier Breaker
Backfeed Breaker
Fuse Block
J11 on UPS
Bypass Module
J10 on UPS
Bypass Module
To UPS
Rectifier Input