Basler Electric BE3-25 Synchronizing Check Relays

INTRODUCTION

BE3-25 sync-check relays are used to ensure that two ac

circuits are synchronized. In order to be synchronized, the

frequency, phase angle, and voltage of the two circuits must

be within preset limits. When this occurs, the BE3-25 output

relay energizes. The primary application of the BE3-25 is to

enable additional generators to be brought on-line without

machine damage or system disturbance. The BE3-25 can

also be used to supervise reclosing or in any instance where

the danger of paralleling two circuits out of synchronism

exists.

APPLICATION:

The BE3-25 series are synchronizing check relays, also known

as paralleling relays. They are used to ensure that two AC

supplies are synchronized. For a system to be synchronized,

the frequency, phase angle, and voltage must be within preset

limits. The BE3-25-****4 can monitor either utility mains bus

bar and incoming generator, or two generators. 

The BE3-25-****4 offers user adjustment of the reset voltage

from 10 to 30%. This voltage corresponds to 6 to 20 electrical

degrees. The unit compares the input voltage and phase

relationship of the bus bar to that of the generator.

When the signal is within the preset limits, the relay energizes.

The BE3-25-****5 operates as the BE3 25-****4.

but has the additional feature of a dead bus facility.

This enables the relay to energize with a generator supply

only, which is a common requirement when utility mains failure

occurs.