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The MM300 integrates protection, control, automation, metering, diagnostics and multiple communication protocols in a rugged compact device for low voltage motor applications. Designed for NEMA and IEC Motor Control Centers, the MM300 delivers superior protection and control to extend equipment life and maximize process uptime.

Key Benefits
  • Full-featured protection for low voltage AC motors
  • Advanced automation capabilities for providing customized protection and integrated process control
  • Advanced FlexLogic™ reduces requirement for local PLC’s
  • Reduced space requirements through integration of multiple devices
  • Application flexibility with multiple I/O options and programmable logic options (FlexLogic™)
  • Enhanced troubleshooting tools including sequence of event records and waveform capture
  • Powerful communications including Serial, Ethernet, Profibus, and DeviceNet protocols
  • Small form factor and remote display options designed to fit in MCC buckets
  • Low Voltage three phase AC motors
  • MCC or stand alone panel mount applications
  • Reversing and Reduced Voltage applications
  • Applications requiring Automation or Control i.e. conveyor systems or well recovery pumps
  • IEC or NEMA class motors

  Key Features    
  • Enhanced Thermal Modeling
  • Mechanical Jam / Stalled Rotor
  • Undercurrent
  • Underpower
  • Acceleration Time
  • Current Unbalance
  • Ground Fault
  • Sensitive Ground Fault
  • Phase Overvoltage / Undervoltage
  • Auxiliary Undervoltage
  • Phase Reversal
  • VT Fuse Failure
  • Thermistor
  • RTD Overtemperature
  Protection & Control
  The MM300 is a digital motor protection and control system, designed for Low Voltage motor applications. Flexible and powerful, the MM300’s protection can be scaled to the specific requirements of your system.
MM300 Block Diagram
  Key Features
  • Metering - current, voltage, power, energy, frequency, RTD, Thermistor
  • Oscillography – analog values at 32 samples/cycle and digital states
  • Event Recorder - Up to 256 time tagged events with 1ms res.
  • Advanced device health diagnostics
The MM300 includes high accuracy metering for all AC signals. Voltage, current, power metering, and temperature all available options. Current and voltage parameters are available as total RMS magnitude and angle.

Log motor operating parameters to allow for analyzing motor loading and performance over prolonged periods of time.
  The MM300’s powerful I/O and programmable flexlogic options offer advanced automation control, reducing the need for additional programmable controllers or discrete control relays.
Flexlogic™ and additional I/O options allow the MM300 to replace local programmable controllers in LV applications, like conveyor belts as in this example
  Key Features
  • Networking Interfaces - Two Wire RS485, RJ45 Ethernet
  • Multiple Protocols (Modbus RTU , Modbus TCP/IP, Internally powered Profibus, ODVA compliant DeviceNet, Profibus DPV1)
  • Programming Ports - USB, RS485
  • Network Time Protocol (when ordered with Ethernet)

The MM300 utilizes the most advanced communications technologies available today making it the easiest and most flexible motor protection relay to use and integrate into new and existing infrastructures. Multiple communication ports and protocols allow control and easy access to information from the MM300. All communication ports are capable of communication simultaneously.

The MM300 supports the most popular industry standard protocols enabling easy, direct integration into HMI and electrical SCADA systems. Modbus RTU is provided standard with a RS485 networking port. The following optional protocols and communication ports are available:

  • Fieldbus Protocol with dedicated port.
    • ODVA Compliant DeviceNet
    • Internally powered Profibus
  • Modbus TCP/IP with RJ45 10/100baseT Ethernet port


The EnerVista™ Suite is an industry-leading set of software programs that simplifies every aspect of using the MM300. The EnerVista™ suite provides all the tools to monitor the status of the protected asset, maintain the relay, and integrate information measured by the MM300 into DCS or SCADA monitoring systems. Convenient COMTRADE and Sequence of Events viewers are an integral part of the EnerVista Setup software included with every MM300, to carry out postmortem event analysis to ensure proper protection system operation.
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