IV404E Rev.000 SIEL S.p.A.
Issue date: 2017-06-05 Pag. 24 di 90 + FR
3.1.6 Backfeed protection
The SAFEPOWER EVO HFT is provided with a device to prevent voltage backfeed on the input line due to
an internal fault. This protection device works by switching off the inverter if the current flow is faulty,
thereby causing voltage backfeed on the by-pass line during operation from the inverter. If the fault occurs
when the UPS is operating from the battery, the load will not be powered.
Should it be required to avoid the shutting down of the inverter in order to keep the load powered by the
inverter even in the event of a double fault, the system can be customized to control the opening coil of a
switch located upstream by reprogramming one of the relays on the
“
REMOTE COMMANDS AND ALARMS
”
card.
The control logic allows the function of the relay to be reconfigured, for example for the backfeed alarm,
and then the free voltage contact can be used to control the triggering of a switch located on the UPS
input.
3.1.7 Emergency power off device (EPO)
The UPS is pre-set to be connected to a remote emergency power off device as laid down in standard EN
62040-1-2. If the remote device (not supplied with the equipment) is activated, the inverter output voltage
is cut.
The connection procedure is shown below.
a - EPO terminal board located on the UPS
b - EPO switch (not provided).
On the SAFEPOWER EVO HFT, the jumper on the EPO terminals (page 29) must be removed, and the wires
from the auxiliary contact of the button must be connected in place of the jumper.
The contact must be closed with the button in the rest position and must open when the button is
pressed.
UPS
a
b
