Emerson 50 and 60 Hz Manuel D’Utilisation

Shielded and double insulated control cables available in lengths of up to 30 meters must be intercon-

nected in a ring configuration between UPS modules as shown below. The parallel control board is 

mounted on the top, behind protective cover of each UPS module (refer to Figure 44). The ring config-

uration ensures high reliability of the control (refer to Figure 31).

Place the UPS modules side by side and interconnect as shown below.
The hot standby mode comprises two series-connected UPS modules of the same rating. One module 

is designated as the hot standby master (downstream), and the other module is designated as the hot 

standby slave (upstream). Their roles are determined by power connection and configuration soft-

ware. In normal operation, both slave and master operate in normal mode and the output from one 

upstream (slave) UPS feeds the bypass input to the other (downstream, master) UPS. The output of 

the downstream (master) UPS is connected to the critical load and is always synchronised to the out-

put of the upstream (slave) UPS. If the inverter of the UPS connected to the load fails, the inverter of 

the upstream (slave) UPS supplies the load through the downstream (master) UPS bypass circuit. 

The system can be programmed to cycle the downstream (master) UPS between normal mode and 

bypass mode so that both UPS units are equally exercised.

Refer to the instructions in 1.0 - Single Module UPS Installation.

NOTE
If it is a hot-standby system, the master must be turned on first.