IV404E Rev.000 SIEL S.p.A.
Issue date: 2017-06-05 Pag. 72 di 90 + FR
BATTERY OPERATION
One battery for each UPS
Each unit draws the energy from its own battery. At the end of its backup time each UPS excludes itself.
The load remains unpowered if the duration of the mains outage is greater than the backup time of the
whole system. When the mains is restored the system will restart automatically. Each SAFEPOWER EVO
HFT recharges its own battery.
One battery for all the UPSs.
Each unit draws the energy from the common battery. At the end of the backup time, the whole system
excludes itself. The load remains unpowered if the duration of the mains outage is greater than the backup
time of the whole system. When the mains is restored the system will restart automatically. Each UPS
recharges the common battery.
OVERLOAD
In this mode too, the devices share the overload equally.
If the load applied to the system is not reduced, the whole system will switch onto the by-pass line. When
the overload is removed, all the units will automatically return to normal operation. If the overload
persists, however, it triggers the external protection devices located at the UPS input on the by-pass line. In
this case the load would remain unpowered.
