Enforces alternator to produce a fixed output voltage
Changes excitation voltage in order to maintain a constant voltage
Prevents alternator damage during engine stopping under load
Provides external voltage adjustment feature
Gets power supply voltage from the input sensing voltage
DATAKOM AVR-40 voltage regulator is an electronic device which lets the alternator to produce a fixed output voltage. The device has open chassis, resin molded design and is intended to be mounted in the alternator terminal box.
The unit does not include moving parts; therefore it is able to operate in highly vibrating environments. The device measures a phase to neutral or phase to phase voltage of the alternator and adjusts the DC voltage applied to the excitation winding until reaching the desired voltage.
The unit offers low-frequency protection feature. A frequency measuring circuit continually monitors the generator output and provides output for low-frequency protection of the excitation system, by reducing the output voltage proportionally with frequency below a manually adjustable threshold.
The nominal frequency can easily be changed to 50 or 60 Hz in the field by push-on link selection. Sensing loss protection circuit terminates the excitation and protects the windings if there is no voltage on the sensing input. The excitation power is derived directly from the generator terminals. The required minimum residual voltage for build-up is 4 V-AC. The output stage of the device is a Half Wave thyristor output associated with a freewheeling diode. Basically the unit is compatible with all brushless type alternators. A stability adjustment potentiometer is also provided for this purpose. A 3V analog input is provided allowing external voltage adjustment.
The AVR has the facility for droop CT connection, to allow parallel running with other similarly equipped generators. An overload protection circuit limits the output current to its nominal value, preventing device failure under overload or short circuit condition.
