A2 Basler Electric Voltage Acceptance Module

The BE1-25A Automatic Synchronizer is a microprocessor based system including features to bring any generator on line in a minimum time, from small diesel units to large difficult hydros. It may be configured for simple manual control systems or equipped for complete automatic control of generators. The BE1-25A initiates closure of the generator circuit breaker when voltage magnitude, slip frequency, and phase difference are within preset limits. This capability minimizes system transients that can result from differences in speed, voltage level, or phase angle at the instant of the breaker closure - transients that can damage the breaker and generating system. The BE1-25A has the ability to operate over a wide range of slip frequencies. This allows it to be used on virtually any type of prime mover, from very slow-responding, high inertia, hydro-turbines to fast-responding gas turbines and diesel engines.


The A2 Voltage Acceptance Module can use as many as three voltage parameters to add constraints to the issuance of breaker command signals. This option is a prerequisite of, and a controller of, any voltage matching option that may be present. The upper Limit control establishes a maximum bus voltage. No closure is to be attempted when the bus voltage is above the upper limit. The lower limit control establishes a minimum bus voltage. No closure is to be attempted when the bus voltage is below the lower limit. The voltage difference control establishes the maximum acceptable voltage difference between the two sides of the circuit breaker (generator voltage minus bus voltage). No closure is to be attempted when the circuit breaker voltage difference is greater than the set limit. The voltage difference is continuously variable over the range of 1 to 10 Vac. An LED to the left of each control lights whenever the associated parameter is beyond the range set by the control. As a result, the breaker closure is inhibited.


When the external dead bus contact is closed, module D1 determines when the bus is dead, and acts upon this determination (if the breaker is detected open) by initiating a close breaker signal. This signal is terminated as soon as the sync acceptor recognizes the breaker as having closed, or when 100 milliseconds has passed (whichever occurs first). The Volts control defines a dead bus condition by establishing a voltage threshold between 10 and 40 Vac. The Dead Bus indicator is an LED that lights whenever the bus voltage is below the control setting.