Description

The MLJ is a digital synchronism check relay that measures bus

and line voltages, checking:

• voltage differences

• frequency slip

• phase angle between both voltages

The main applications of the MLJ are:

• connection of a generator to the network

• reestablishing the connection between two parts of the

network

• manual closing of breakers

The relay sends a closing output to the breaker when all of the

values fall within the set limits and maintain these values for a

period of time which has been set by the user. If any of the

condi tions are not met, the relay will provide a close condition

fault signal.

The relay has two operational modes:

• a continuous mode in which itconstantly checks the synchro

nism

• the manual mode is activated when voltage is applied to a

manual digital input, initiating the synchronism supervision

when voltage is applied by another check starting digital

input