MVC4 Medium Voltage Soft Starter

The MVC4 Medium Voltage Series Soft Starter is designed to start AC motors in any fixed speed application. It provides maximum protection with "True Thermal Modeling," while allowing smooth, stepless control of acceleration and deceleration. The MVC4 Series guarantees power control and protection for your most important assets.

AC Supply Voltage:
2300, 3300, 4160, 6000/7200V, 11-15kV
+10% to -15%, 50/60 Hz line voltages

HP Ratings:
Up to 10,000HP @ 7.2kV (800 Amps max)
Up to 20,000HP @ 15kV (800 Amps max))

Overload: 500% - 60 seconds, 600% - 30 seconds

Call us for pricing and availability

Soft start & protect any AC motor

Motor and starter protection is taken to a new level by combining a high-end motor protection relay with a heavy duty solid state starter. Flexible control features and selectable ramping profiles to match any application... no need to compromise performance. High level circuit isolation via fiber optics (standard on all units) for safety and power quality immunity. Sealed NEMA 12 enclosures are standard equipment, not an expensive option.
Soft start & protect any AC motor.

The MVC4 Series starter is designed to start AC motors in any fixed speed application. It provides maximum protection with "True Thermal Modeling," while allowing smooth, stepless control of acceleration and deceleration. The MVC Plus Series guarantees power control and protection for your most important assets.

Heavy-duty attitude highest rated power devices for maximum current carrying capacity. Rated at 500% for 60 seconds, the MVC4 Series starter will never be the limiting factor in your application. Powerful sustained gate pulse insures reliable SCR firing without reactors (unlike "wimpy" pulse train designs that require a reactor to prevent SCR and motor damage) .


Bullet Advanced motor protection relay and ramp features programmable via the keypad or a laptop computer.

Bullet Fiber optically isolated low voltage compartment with up to 110kV BIL rating for safety and reliability.

Bullet Built-in 120V control power transformer*; voltage and current metering.

Bullet Load-break / fault-make rated disconnect switch with door safety interlocking.*

Bullet Visible grounding bar for safe operation.

Bullet Coordinated motor fuses with blown fuse indicators.

Bullet Line isolation vacuum contactor.*

Bullet Fully rated bypass contactor for increased thermal capacity and optional across-the-line starting.

Bullet Heavy duty SCR stack assemblies with ring transformer isolation for reliable SCR gate firing.

Bullet RTD Option accepts up to 12 RTD inputs.

Bullet Zero sequence ground fault protection option.

Bullet Top entry, bottom exit with room for stress cones.

Bullet Removable entry plates for easy connections.

Bullet NEMA 12 gasketed enclosure (NEMA 3R optional).

Advanced Protection

Bullet True Thermal Modeling monitors the motor for excessive thermal conditions due to starting, running and even ambient conditions.

Bullet Retentive Thermal Memory for continuous overload protection even after a complete power loss.

Bullet MVC Plus remembers the last thermal condition of the motor, observes the off time via a real-time clock and adjusts the thermal model accordingly.

Bullet Non-Volatile Memory stores the thermal memory without the need for batteries.

Bullet True Time Thermal Tracking adjusts the thermal model for different cooling rates based on motor temperature, running state or power loss.

Bullet Dynamic Reset Response Reset is only allowed after the motor has sufficient thermal capacity for a successful restart.

Bullet Thermal Model Biasing adjusts for heating effects of phase current imbalance or optional RTD inputs.

Bullet Flexible Setup Choose the level of overload protection.

Bullet Programmable Trip Classes selectable from NEMA/UL Classes 5 - 30.

Bullet Dual Mode Protection separate trip curves for start and run modes (example: Class 20 for start, Class 10 for run).

Bullet Warning Levels can be programmed and assigned to one of six built-in output relays.

Bullet Custom Trip Curve programmable based on the motor manufacturer’s data

Bullet Remote or Automatic Overload Reset can be activated for unattended operations.

    AC Supply Voltage
    2300, 3300, 4160, 6000/7200V, 11-15kV VAC +10% to -15%, 50/60 Hz line voltages

    HP Ratings
    Up to 10,000HP @ 7.2kV (800 Amps max)
    Up to 20,000HP @ 15kV (800 Amps max)
    Contact factory for higher rating requirements

    SCR Overload Ratings
    500% - 60 seconds, 600% - 30 seconds

    Power Circuits
    Series strings of SCR powermodules (1, 2 or 3matched pairs of SCRs per phase depending on voltage rating)

    SCR Peak Inverse Voltage
    Line Voltage 2,300V, PIV Rating 6,500V
    Line Voltage 3,300V - 4,160V, PIV Rating 13,000V
    Line Voltage 6,000V - 7,200V, PIV Rating 19,500V
    Line Voltage 11,000V - 15,000V, PIV Rating 39,000V

    BIL Rating
    2,300V - 7,200V: 60kV
    11,000 - 15,000V: 110kV

    Transient Voltage Protection
    dv/dt circuits (1 per SCR pair)

    Vacuum Bypass Contactor
    Standard on allmodels, line start rated

    Ambient Operating Conditions
    0 - 50°C (82° F to 122° F) (Optional -20° to 50° C with heaters)
    5 - 95% relative humidity
    0 - 3300 ft (1000m above sea level without derating)

    Digital Control Unit (DCU)
    Programmable keypad/operator with 2 lines x 20 character backlit LCD display. Status/Alarm LEDs (indicate: Power, Run, Alarm, Trip, Aux 1 - 8)

    Auxiliary Contacts
    Multiple FormC contacts rated 5A @ 250VACmax. 6 fully programmable relays (including fail-safe operation) 5 dedicated relays (fault, at-speed, etc. )

    Programmable Features
    Motor FLA, service factor, insulation class
    Dual Ramp Adjustments - Two independent settings for:
    Initial Torque 0 - 100% of nominal torque, voltage or current
    Current Limit 200 - 600% of motor FLA
    Acceleration Time 1 - 120 seconds
    Three Custom Curves Via plotted torque/time axis points
    Pump-Flex Decel 1 - 60 seconds with begin & end torque adj
    Kick Start 0.1 - 2.0 seconds (10 - 100% voltage)
    Tach Feedback (option) Closed loop speed ramp

    Motor and Starter Protection
    Electronic Overload, Phase Loss
    Phase Imbalance, Phase Reversal
    Short Circuit Detection, Over / Under Current
    Over / Under Voltage, Shorted SCR / Shunt Tri
    p Starter Over-Temp, Coast Down Lockout
    Starts per Hour Lockout, Time between starts
    RTD Input (Option), Ground Fault (Option)g

    Statistical Data
    Elapsed run time, last start time, average starting current, stores history of up to 60 events (data includes date & time, phase & ground fault current). Also displays time-to-trip, remaining inhibit time and starts/hour values.

    Metering (Voltage & Current)
    Percent of FLA, phase currents, kVAR, kVA, kW, power factor, demand, avg. start current, remaining thermal register, thermal capacity to start,measured capacity to start, time since last start, line frequency, phase order, RTD values (optional)

    NEMA 12 with 3R optional (not for direct sun applications), top and bottom entrance plates, 11 gauge steel, ASA #61 gray powder coated paint

    RS485 with Modbus RTU protocol or RS232 with windows interface

    Available Communications Options: Ethernet/IP, Modbus TCP, DeviceNet Profibus DP, PROFINET