SPA140C-DA Spau 140 c Synchro-check继电器

Synchro-check relay for checking the conditions at circuit breaker closing
One synchro-check relay is capable of checking the close conditions of two separate circuit breakers.
Synchro-check function for checking synchronism when live lines/busbars are to be connected together.
Voltage-check function for checking energizing conditions. Four energizing directions selectable for each circuit breaker.
Two control modes available: continuous mode operation for applications where the synchrocheck relay gives the close permission to another module (e.g. the control module) and command mode operation for applications where the relay closes the circuit breaker via its own control output.
Alarm signal for failed CB closing at command mode operation Continuous self-supervision of both hardware and software Serial port for connecting the relay to the electrical or optical SPA bus

The synchro-check relay SPAU 140 C is an integrated microprocessor-based voltage measuring relay designed to be used for checking the conditions for circuit breaker closing. The relay can be used for closing ring mains, interconnecting busbars and connecting generators to the network

The relay incorporates two identical stages which operate as independent units. Both stages of the synchro-check relay has two parallel functions: a synchro-check function and a voltagecheck function.
The synchro-check relay can be used for two different operating conditions, the most typical of which is where both sides of the circuit breaker to be closed are live. Then synchronism is always checked before the circuit breaker is given the permission to close. The other situation is where one or both sides of the circuit breaker to be closed are dead and, consequently,
frequency and phase difference cannot be measured. In this case the relay checks the energizing direction. The user is able to define the voltage range within which the measured voltage is determined to be “live” and “dead”.
The purpose of the synchro-check function is to find the instant when the voltages on both sides of the circuit breaker are in synchronism.
The conditions for synchronism are met when the voltages on both sides of the circuit breaker have the same frequency, are in phase and are of such a magnitude that the concerned busbars or lines can be regarded as live.
When the frequency, phase angle and voltage conditions are fulfilled, the duration of the synchronizing conditions is checked so as to ensure that they will still be met when the contacts of the circuit breaker close. This duration is determined on the basis of the frequency and phase difference measured. Depending on the circuit breaker and the closing system, the delay from the moment the closing signal is given until the circuit breaker finally closes is about 50 – 250 ms. The CB operate time selected tells the relay for how long, at least, the conditions have to persist.