Cummins STAMFORD MX341 AVR Automatic Voltage Regulator generator system

Cummins STAMFORD MX341 is an automatic voltage regulator with excellent performance. Here is a detailed introduction:

Functional features

High-precision voltage regulation: By detecting the voltage of the main winding of the generator, using two-phase induction and three-phase RMS detection, it can accurately control the power provided to the stator and main rotor of the exciter, stabilize the output voltage of the generator within the specified range, and the voltage regulation accuracy can reach <±1% (engine speed variation within 4%).

Multiple protection functions:

Underspeed protection: The frequency measurement circuit monitors the generator shaft speed in real time. When the speed is lower than the preset threshold, the generator output voltage is proportionally reduced to protect the excitation system. It also has an adjustable volt/hertz slope to improve the frequency recovery time of the turbocharged engine.

Overexcitation protection: By internally shutting down the AVR output device, uncontrolled overexcitation is limited to a safe period until the generator stops.

Overvoltage protection: With overvoltage protection function, it can shut down the internal output and provide a set of outputs to trip the MCCB.

Short-circuit limiting function: It can control the continuous short-circuit current, and the maximum excitation energy can be limited to a safe range by shutting down the output internally.

Good stability and adaptability: The excitation power supply is taken from the three-phase permanent magnet generator (PMG), which protects the AVR control circuit from nonlinear loads and RF interference from the generator terminals. It can withstand the generator short-circuit current and provide a stable voltage output for the generator to adapt to various working conditions.

Strong adjustability: It is equipped with an adjustable slow start circuit to control the smooth establishment of the generator output voltage. It provides a remote voltage regulator connection to facilitate users to accurately control the generator output. It also provides an analog input terminal that can be connected to the Newage power factor controller or other output-compatible external equipment, and there is a device connected to the CT, which can be connected to other generators with similar devices.

Technical parameters

Input voltage: The inductive input voltage is 190-264V AC max, 1 phase 2 wire, frequency 50-60Hz nominal; the power input (PMG) voltage is 140-220V AC max, 3 phase, 3 wire.

Input current: Power input current is 3A/phase, frequency 100 - 120Hz nominal.

Output parameters: Output voltage maximum 120V DC, continuous current 2.7A, intermittent 6A for 10 seconds, minimum resistance 15ohms.

Other parameters: Thermal drift is 0.03% for every 1℃ change in AVR ambient temperature; soft start ramp time is 3 seconds; in typical system response, AVR responds 10ms, excitation current takes 80ms to 90%, and motor voltage takes 300ms to 97%; operating temperature is -40℃～70℃, storage temperature is -55℃～80℃, relative humidity is 95% (non-condensing) at 0-70℃.

Application scenarios

It is often used in Cummins' STAMFORD® P6, STAMFORD® P7 and STAMFORD® S7 series AC generators, and is widely used in the fields of industry, commerce, and electricity to provide stable power for various electrical equipment and ensure the normal operation of the equipment.