Legrand TRIMOD HE 15 kVA [8/14] Operating principle

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To protect the batteries from damage due to deep discharges1 the minimum tolerated battery voltage

limit2 is automatically changed to suit the applied load (default setting), while allowing the user to select

a type of management with fixed voltage limits.

The “average battery life is 6 years3.

3.4 Digital Display e Alarm signal

UPS will be equipped with a backlighted alphanumerical liquid crystal display (LCD), with 20 characters

on 4 lines. This display is built into the front part of the UPS where there is also an ultra-bright operating

status indicator which shows the operating status and any alarm conditions by means of a traffic light

code.

Four simple buttons situated near the display allow the user to:

• display the operating data (ref. sect 2.2 Measurements)

• enter the operating parameters (ref. sect. 2.3 Adjustments);

• select the language in which the messages are given.

4 OPERATING PRINCIPLE

The purpose of this section is to define the various different operating conditions of the UPS.

4.1 Normal service condition

In normal conditions, UPS runs in the double conversion on-line mode, thus the users are powered in an

uninterrupted way by the inverter, which is powered by the electricity main through the AC/DC converter

(rectifier/PFC) that automatically corrects the power factor on the UPS input as well.

The inverter is constantly synchronized with the electricity main so as to allow the bypass to function

correctly during mains/inverter and inverter/mains commutations. These commutations may be

necessary if an overload occurs or if the inverter stops.

The battery charger in each power module provides the power required to keep the battery charge at an

optimum level.

4.2 Inverter stopping or overload

4.2.1

Inverter stopping

If the inverter stops, the user is automatically transferred without interruptions to the primary main by

means of the automatic bypass.

4.2.2

Overload

When a temporary overload occurs on the load side of the UPS, current monitoring allows the UPS to

withstand the situation within certain limits, without the automatic bypass having to be used: if the

overload lasts a long time or exceeds the limits preset by the current monitoring device, the user is

transferred without interruptions to the primary main by means of the automatic bypass and then returns

to the inverter once the overload has terminated.

4.2.3

Bypass activation sensitivity adjustment

prolonged discharges with a low load

2 voltage that causes the inverter to switch off owing to end of runtime

3 depending on the operating temperature, the number of charging/discharging cycles, etc.