Details:

• The MX321TM analogue, 3-phase sensing, permanent magnet generator (PMG) powered automatic voltage regulator (AVR) provides isolation from the effects of non-linear loads, improved motor starting performance and sustained short circuit current.
• The MX321TM AVR is provided as standard for the STAMFORD® S6 and HC6 alternators and can also be provided as an option across the STAMFORD® range. To ensure your MX321TM AVR is genuine, purchase it from an authorized NEWAGE® | STAMFORD® | AvK® dealer.
• MX321™ is a three phase sensed Automatic Voltage Regulator and forms part of the excitation system for a brush-less generator. Excitation power is derived from a three-phase permanent magnet generator (PMG), to isolate the AVR control circuits from the effects of non-linear loads and to reduce radio frequency interference on the generator terminals. Sustained generator short circuit current is another feature of the PMG system.
• The AVR senses the voltage in the main generator winding and controls the excitation to maintain the generator output voltage within the specified limits, compensating for load, speed, temperature and power factor of the generator. Three phase RMS sensing is employed for superior voltage regulation.
• Adjustable Soft start circuitry is included to provide a smooth controlled build up of generator output voltage. A frequency measuring circuit continually monitors the shaft speed of the generator and provides under-speed protection of the excitation system by reducing the generator output voltage proportionally with speed below a pre-settable threshold. A further enhancement of this feature is an adjustable volts per Hertz slope and voltage recovery time, to improve the response of turbo charged engines.
• Current limiting may be included to allow control over the amount of sustained short circuit current. Maximum excitation is limited to a safe period by internal shutdown of the AVR output device. This condition remains latched until the generator has stopped. The AVR includes an over-voltage protection feature with internal shutdown of the AVR output device, plus the ability to trip an optional excitation circuit breaker if required. Provision is made for the connection of a remote voltage trimmer, allowing the user fine control of the generator’s output.
• An analogue input is provided allowing connection to a Newage Power Factor controller or other external device with compatible output.
• Potential Divider and Rectifier takes a proportion of the generator output voltage and attenuates it. The potential divider is adjustable by the AVR Volts potentiometer and  external hand trimmer (when fitted). The output from the droop CT is also added to this signal. A rectifier converts the a.c. input signal into a d.c. signal representing generator voltage.
• The AVR has the facility for droop CT connection, to allow parallel running with other similarly equipped generators.
• The DC Mixer adds the Analogue input signal the generator voltage signal.
• The 3 Phase Rectifier converts the output of the current limit CT’s into a dc signal representing generator current.
• The Amplifier (Amp) compares the generator voltage or current signals to the Reference Voltage and amplifies the difference error to provide a controlling signal for the power devices. The Ramp Generator and Level Detector  and Driver infinitely control the conduction period of the Power Control Devices and hence provides the excitation system with the required power to maintain the generator  voltage within specified limits.
• The Stability Circuit provides adjustable negative ac feedback to ensure good steady state and transient performance of the control system.
• The Power Supply provides the required voltages for the AVR circuitry.