Check Synchronising Relay Block MAVS02

Features and technical specifications:

1. Optional undervoltage blocking and differential voltage blocking features available
2. Low burden
3. Wide range of phase angle setting adjustments
4. Wide range of slip frequency timer settings
5. Zero and infinity settings available on timer
6. Live line/dead bus and dead line/live bus conditions can be independently selected to cause operation of the output relay.
7. Auxiliary supply can be ac or dc
8. Front mounted led indicates when output relay is operated
9. Suitable for phase to neutral or phase to phase connections

This Check Synchronising Relay Block is easily insert in your schematic diagram and connect as you like way.

The incoming line and bus voltages are stepped down by two internal VTS and squared by operational amplifiers. An exclusive OR circuit gives an output when the square waves are of opposite polarity, which charges a capacitor to a level proportional to the duration of the exclusive OR output and hence to the phase difference between the
incoming voltages. The capacitor discharges to zero while the exclusive OR output is off. A level detector monitors the voltage on the capacitor allowing the timer to operate for in-phase conditions and disabling the timer for phase
differences greater than setting. A feedback circuit maintains the output of the level detector while the capacitor is discharged. The phase angle setting is adjusted by changing the value of resistance through which the capacitor charges. Auto-reclose is a good example of such a switching operation. Depending on the size of load transfer and length of line, relatively large differences in magnitude and phase angle can exist between the voltages on either side of the circuit breaker. The relay is set to the maximum phase angle and voltage differences which allow the circuit breaker to close without an unacceptable level of disturbance in the system. There should not be any frequency difference but a slip frequency check is often incorporated to ensure that the two parts to be interconnected have not been totally isolated electrically. The auxiliary supply voltage is passed through a bridge rectifier, to allow either ac or dc supplies to be chosen. Note that the auxiliary supply must be specified as ac or dc by customer (see Technical Data). In a 30/34V relay the output of the bridge rectifier feeds a series regulator, which produces stabilised rails of +12V and +24V for the measuring circuits, and the dc supply for the output relay which is driven from a constant current source when an output signal is given by the measuring circuits. A capacitor smooths the ac input and holds the voltage if a supply interruption of up to 10ms occurs. In high voltage versions a second series regulator drops the incoming voltage to an intermediate level for the relay drive circuit.