Mega MEg40+, Руководство пользователя

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Uninterruptible power supply MEg102
are galvanically isolated by transformers, they are to be connected to the power supply
unit using screw-on terminals. There is a button on the outside of the plastic cover to stop
the battery operation.
The principle of the uninterruptible power supply MEg102 is represented by the group
diagram in Fig. 1. The input voltage U
inp
applied to the terminals IN is converted by
the transformer T1 and the subsequent rectifier to the DC voltage, which is converted
by means of a synchronized generator and output switches to the AC pulse voltage and
transformed to U
outp
by the transformer T2 to power supply the instrument. The voltage
U
outp
is on the terminals of the power supply unit MEg102.
The U
inp
voltage drop below the lower limit indicates with the SitOK signal to the control
circuits of the accumulator to change over the battery supply. The battery operation is
finished when U
inp
returns above the lower limit plus necessary hysteresis or when the
period set by the internal generator expires (default 180 sec) or when the external button
Battery stop
is pressed for about 2 seconds.
Fig. 1: Group wiring diagram of uninterruptible power supply MEg102.
Battery control
Output
switches
SitOK Upom
Upom Sync
Control signal generator
U inp U outp
T1 T1
+
Bat
+
Bat tery
T2 T2