MaxPower Corp Gamatronic Power+ M50-RM - Manual (Page 34)

Gamatronic Electronic Industries Ltd.
POWER+ RM 50 K VA, N.Am. Std. – User Guide, Release 1.9 18
3. O
PERATING MODES
The POWER+ UPS functions to supply AC electrical power to your load.
While using the POWER+, three modes of operation are possible:
 Normal
operation
 Battery
operation
 Bypass
operation
All three operation modes are encountered during normal UPS use to constantly provide
regulated voltage to the load.
In the normal operation mode, the UPS provides total power protection for the load.
In the battery operation mode, the load power is supplied by the battery.
In the bypass mode, power is transferred directly from the ac input to the load, bypassing the
inverter. In this mode, there is no protection but it is useful for short-term operation. When power
is restored, the UPS returns to normal operation.
In addition to the three operation modes that are set automatically by the UPS, two additional
modes can only be invoked via manual intervention: by either the user or a technician:
 Maintenance
bypass
 Emergency Power Off (EPO)
Details of each mode of operation are described in the sections below.
3.1 Normal operation
The UPS is almost always in normal operation mode. The load receives its power from the
inverters that supply stabilized voltage, protected from spikes and irregularities in the AC input.
The AC input system feeds the charger that supplies DC power to the inverter, while concurrently
charging the batteries.
3.2 Battery operation
In the event of an ac line failure, the load continues to receive power from the inverters, but the
DC input to the inverter is taken from the batteries, instead of from the rectifier.
The batteries are galvanically connected by DC link to the inverter and the charger. The DC
inherently remains constant when the AC input supply drops out, without any switching devices.
The duration of the battery operation is determined by the load demand and the battery capacity.
3.3 Bypass operation
During bypass operation, the load receives power directly from the AC input via the static switch.
Whenever the inverters cannot provide power to the load, either due to an overload or a short-
circuit in the load, transfer to the AC input is automatic. As soon as the problem is corrected, the
load is transferred back to the inverter.