Wisconsin Parts Database Instructions and Discussion Team/Group > WISCONSIN
> Machine Parts
> Replace
> Used
> With Warranty
> New cummins age used voltage regulator MX321 305-0823
New cummins age used voltage regulator MX321 305-0823
USED GOOD CONDITION ORIGINAL MX321 VOLTAGE REGULATOR. STAMFORD, NEWAGE, AVK AND CUMMINS. 90 DAY WARRANTY AND FREE TECH SUPPORT INCLUDED
General description Technical specification
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 nonlinear
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
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
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
An analogue input is provided allowing connection to a
Newage Power Factor controller or other external device
The AVR has the facility for droop CT connection, to allow
parallel running with other similarly equipped generators.
Voltage 190-264V ac max, 2 or 3 phase
Voltage 170-220V ac max, 3 phase, 3 wire
Current continuous 3.7 A (see note 1)
+/- 0.5% RMS with 4% engine governing (see note 2)
0.02% per deg. C change in AVR ambient (note 3)
+/-10% with 5 k ohm 1 watt trimmer (see note 4)
Max. Dwell 20% volts/S recovery
Maximum input +/- 5 Vdc (see note 6)
Sensitivity 1v for 5% Generator Volts (adjustable)
Max. sensitivity: 0.22 A for 5% droop 0PF
Set point: 300v. Time delay: 1 Sec (fixed)
CB trip coil resistance: 20-60 ohms
Time delay 8-15 seconds (fixed)
Operating temperature -40 to +700C
Relative Humidity 0-700C 95% (see note 7)
Storage temperature -55 to +800C
1. Derate linearly from 3.7A at 50 C to 2.7A at 70 C
2. The stated voltage regulation may not be maintained in the
presence of certain transmitted radio signals. Any change in
regulation will fall within the limits in Criteria B of
4. Applies to Mod status E onwards. Generator de-rate may
apply. Check with factory.Factory set, semi-sealed,
5. Any device connected to the analogue input must be fully
floating (galvanically isolated from ground), with an
insulation strength of 500V ac.
