Environment information, Signal reception

Environment information

Terminals XR2, XR3, XR4 and XR5 on the "Media Contacts 11" board of each type of unit can be used to receive signals from the operating environment and to transmit signals concerning the operating status of the UPS (see figure 16 for the position of the board, item 12).

Signal reception

The signals should be provided by volt- free contacts.

◗emergency off:

An NC contact causes shutdown of the inverter and the rectifier/charger, opening of the battery circuit breaker and activation of a relay contact on the "Media Contacts 11" board;

◗battery room ventilation fault:

An NO contact causes shutdown of the rectifier/charger;

◗battery circuit breaker QF1 closed: An NO contact prevents inverter start- up if the circuit breaker is open;

◗battery temperature:

A PC-board, placed near the battery, supplies information on the battery temperature, thus enabling the rectifier/ charger to regulate the battery voltage;

◗"auxiliary" signals:

Depending on the selected settings, these signals may be used to provoke:

◗forced shutdown of the inverter (whatever the status of the bypass AC source),

◗protected shutdown of the inverter (load transfer to the bypass AC source),

◗a change in the inverter output frequency (50 Hz or 60 Hz).

◗limiting of the current drawn by the rectifier/charger (programmable value) when supplied by an engine generator set with an insufficient power rating. The additional power required by the inverter is supplied by the battery which discharges,

◗limiting of the battery charge current (programmable value) if the normal AC source is replaced by an engine generator set with an insufficient power rating.

Signal transmission

◗an auxiliary 24 V power supply, isolated and backed up, is used to supply:

◗the undervoltage release of the battery circuit breaker(s) QF1,

◗the board that measures the temperature in the battery room;

◗"low battery" warning signal (volt- free changeover contact) indicating that battery time is about to run out. The warning threshold may be personalised;

◗"load on UPS" signal (volt-free changeover contact) indicating that the load is supplied by the inverter. For a single-UPS unit, one volt-free changeover contact may be used to indicate that the load is supplied by the bypass AC source;

◗"load on battery power" signal (volt-free changeover contact) indicating that the inverter is supplied by the battery in the following cases:

◗normal AC source outage or voltage drop,

◗rectifier/charger shutdown,

◗rectifier/charger current limiting.

This signal, which may be used to initiate process saving and shutdown procedures, is time-delayed 30 seconds to avoid unnecessary operations following micro-breaks;

◗"maintenance position" signal (volt-free changeover contact) indicating that:

◗maintenance bypass switch Q3BP is closed,

◗bypass AC source input switch Q4S is open,

◗inverter output switch Q5N is open,

◗battery circuit breaker QF1 is open;

◗signal to open battery circuit breaker(s) QF1 in the event the "emergency off" button is pressed or to avoid an excessive battery discharge (lasting more than three times the rated backup time plus two hours);

◗full-shutdown contact (volt-free changeover contact) used to trip switching devices in the event of an emergency shutdown or a full shutdown (button 7 ).

◗"general alarm" information (volt- free changeover contact) which includes:

◗internal faults,

◗information on temperatures outside tolerances in the battery room (optional),

◗overload information (> In),

◗static-switch ventilation and power- supply faults.

Note:

◗The maximum breaking capacity of

the changeover contacts is 5A at 250V;

◗information on the battery is not supplied to frequency converters without a battery.

APC 20 - 200 KVA user manual Environment information, Signal reception, Signal transmission