G-Tec Saturn, Manual

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40
OPERATION
O
PERATION FROM MAINS
UPSs connected in parallel share the current absorbed by the load. In a system with several UPSs connected in parallel there is
a single MASTER unit with the other units being SLAVE units. The UPSs are identical and the selection of MASTER takes place
automatically at power up.
The UPS identifier, made up of a number between 0 and 7 followed by a letter, is displayed on the top left of the measurements
readout pages. The letter “M” indicates the Master unit while the letter “S” the Slave units. The units are enumerated automatically
and randomly on power-up. On power-up each UPS acquires a unique identifier which is different to those of the other UPSs
already powered-up.
The MASTER and SLAVE units can exchange their roles during normal operation in the event of system configuration changes
(fault, Master UPS isolation, inverter synchronized switch-on and switch-off). The locking of a unit determines its automatic
isolation and the load is distributed between the remaining active units; if the power output is excessive for the remaining UPSs,
the system logic switches all the units, even the isolated UPS, onto the bypass line.
The ECO (LINE INTERACTIVE), SMART (SMART ACTIVE), STBYOFF (STAND-BY OFF) operating modes are not available at
present if the parallel card is installed (parallel mode).
O
PERATION FROM BATTERY
SEPARATE BATTERIES
Each unit takes its energy from its own battery. Once the backup time is over, each UPS isolates itself.
The load remains without supply if the duration of mains failure is longer than the backup time of the entire system. When the
mains returns, the system will start up again automatically (only if the Auto-restart function is activated). Each UPS charges its
own battery.
COMMON BATTERIES
Each unit takes energy from the common battery. Once the backup time is over, the whole system isolates itself. The load remains
without supply if the duration of mains failure is longer than the backup time of the entire system. When the mains returns, the
system will start up again automatically (only if the Auto-restart function is activated). Each UPS charges its own battery.
O
VERLOAD
Also in this mode the units share the overload in equal percentages.
An overload on one unit (if this remains for a longer period than is permissible) causes the whole system to switch onto the bypass
line. When the overload is removed, all units return automatically to normal operation after about 2 minutes. If the overload remains
this causes the bypass to be blocked or external protections at the UPS input on the bypass line to be triggered. In this case the
load remains without power
A
SYNCHRONOUS START
-
UP PROCEDURE
Switch on all the UPS units in the parallel system and wait until they have all gone into STAND-BY status. After, close all the
SWOUT output disconnecting switches. Switch on each UPS using its own control panel. On initial start-up, each UPS auto
calibrates for approximately one minute during which phase (“STATUS: STARTING”) the load is not powered.
If all units are switched on within 5 s, the load is powered synchronously by all the UPSs. Otherwise, each UPS will start powering
the load after its auto calibration.
To avoid overload of single units, make sure the load is connected to the parallel system only on termination of the auto calibration
of all units (STATUS: LOAD ON INVERT.”).