TECHNICAL MANUAL
942088.001
942088.001 - 24/09/98
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3.- BASIC
OPERATION.
“POWER START” has no ON/OFF switch, when the mains voltage is present the unit
automatically starts up. The UPS can turn its output off by the “TIME PROGRAMMER” or by
“AUTO-OFF”.
During the start up, the UPS does an “AUTOTEST”, if the battery, internal circuits and
the mains are correct, it will connect the relays supplying voltage to the output.
The microprocessor continually checks the mains, when it fails, the inverter supplies
AC power to the load. The load normally operates until the battery is exhausted. The UPS
automatically transfers the load back to the mains power and recharges the batteries when
the mains voltage returns to normal.
The UPS provides automatic voltage regulator in two steeps, central and boost. It
corrects low input voltage without drawing power from the battery. Even with low input
voltage the unit can recharge the battery.
The commutation between steps is performed using relays. The unit will turn to
batteries for a few seconds, thus the commutation time will be lower.
The UPS operation is fully controlled by a microprocessor that is continuously
checking all the parameters and processes:
- Battery voltage.
- Output current (only on inverter).
- Mains input voltage, zero crossing points and phase.
- Output voltage.
- Vigilance of the internal voltages.
- Vigilance of the inverter.
- Relays (back - feed and voltage regulation)
- Charger of the battery
- RS232 Communication
Explanation about the types of switching off the UPS:
1.- AUTO-OFF : Automatic switch off. When the UPS is working on battery and the output
current is lower than the “MINIMUM THRESHOLD” the UPS will turn its output off after 30
seconds. The unit starts up again when the mains is present.
2.- Switch off by SOFTWARE. There are three possible commands :
•
IMMEDIATE switch off: the UPS will immediately cut its output off after receiving this
command. The UPS will remain in “STAND-BY” mode. The UPS can be only started up
using the “START UP” command.
•
PREWARNING switch off: the UPS will go on batteries for a period of time equal to the
“PREWARNING TIME”, and then the unit will stop. The UPS will remain in “STAND-BY”
mode. The UPS can be only started up using the “START UP” command.
•
TOTAL switch off : After receiving this order the UPS cuts its output voltage and its
internal power supply off. With this switch off mode the UPS losses the date the time and
cannot communicate with the computer. It will start up when the mains come back.
