MX350 Controller

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The MX350 controller is specifically designed for low voltage Automatic Transfer Switch (ATS) applications. The flexible control and communications options are ideal for any application. Integrated push buttons, graphical controls and LED indicators reduce external components and wiring in addition to providing local control and access to system information. Multiple communication protocols allow simple integration into monitoring and control systems.

Controller Specifications

  • Communications Interface - Optional Serial RS-485 upt to 115.2 Kbps or TCP/IP (10/100 base-T) Serial RS-485 upt to 115.2 Kbps or TCP/IP (10/100 base-T)
  • Control Power 120 VAC 120 VAC
  • Delay NeutralTransition Time Delays (DT,DW) 0-10 minutes 0-10 minutes
  • Delay Transfer to Nonpreferred Source (W) 0-5 minutes 0-5 minutes
  • Delay for Engine Cool Down (U) 0-60 minutes 0-60 minutes
  • Load Control Relay Contacts (1) rated for 10A @ 24VDC or 120VAC rated for 10A @ 24VDC or 120VAC
  • Load Control Relay Contacts (2) 0-259 minutes 0-259 minutes
  • Operating Temperature Ambient (-20˚C to 50˚C) (-20˚C to 50˚C)
  • Overfrequency Dropout for Source 1 and Source 2 50.1 - 63 Hz 50.1 - 63 Hz
  • Overfrequency Restore for Source 1 and Source 2 50 - 62.9 Hz 50 - 62.9 Hz
  • Overvoltage Dropout for Source 1 and Source 2 105 - 110% of nominal 105 - 110% of nominal
  • Overvoltage Restore for Source 1 and Source 2 103 - 108% of nominal 103 - 108% of nominal
  • Source Sensing 120 - 690 VAC +/- 1% of nominal voltage (+/- .05 Hz, +/-.5 A) 120 - 690 VAC +/- 1% of nominal voltage (+/- .05 Hz, +/-.5 A)
  • Storage Temperature (-40˚C - 90˚C ) (-40˚C - 90˚C )
  • Underfrequency Dropout for Source 1 and Source 2 45 - 59.9 Hz 45 - 59.9 Hz
  • Underfrequency Restore for Source 1 and Source 2 45 - 59.5 Hz 45 - 59.5 Hz
  • Undervoltage Dropout for Source 1 and Source 2 75-99% of nominal 75-99% of nominal
  • Undervoltage Restore for Source 1 and Source 2 85-100% of nominal 85-100% of nominal
  • Voltage Unbalance for Restore for Source 1 and Source 2 4 to 19% of nominal 4 to 19% of nominal
  • Voltage Unbalance on Dropout for Source 1 and Source 2 5 to 20% of nominal 5 to 20% of nominal

Technical Summary

  • Rating Range Switch Dependent Switch Dependent
  • Switch Type Application Dependent Application Dependent
  • Transfer Type Application Dependent Application Dependent

Features and Benefits

  • Dual Communications
    Built-in RS-485 serial and 10/100 base-T Ethernet
    Open protocols - Modbus RTU and Modbus TCP
  • Available to support Open, Closed and Delayed Transition
  • Small footprint
  • Graphical control panel
  • Multiple communication protocols
  • ¼ inch VGA color graphical display with embedded HELP menus
  • Status LED's indicating:
    ALARM - indicating a problem with the ATS or a user configured alarm condition is active
    TD DELAY - indicating the controller is timing before taking the next control action
    XFER INHIBIT - indicating the controller will not transfer to the other source without operator intervention
    SOURCE 1(S1) AVAILABLE LED - indicating power is present per user setpoints
    SOURCE 2 (S2) AVAILABLE LED - indicating power is present per user setpoints
    SOURCE 1 (S1) STATUS LED - indicating load is connected to S1 power
    SOURCE 2 (S2) STATUS LED - indicating load is connected to S2 power
  • User-Configurable setpoints for inputs and Outputs
  • Field modification of control features
  • Plant exerciser clock for 1 day, 1 week, 14 days, 28 days or 365 days. The time base of 365 days permits up to 24 events to be scheduled and the other time bases permit up to 24 events.
    Fast Test - test with load, no time delays
    Transfer Load - test with load with time delays
    No Transfer - test without load, generator start only
  • Controller Power Supply utilizing the Universal Transformer Assembly (UTA) - provides 170Vdc to the controller and 24Vdc ungrounded to the power relays. The UTA also provides line voltages from 120Vac to 600Vac via an internal six position jumper array, 120Vac UPS input and 24Vdc input battery options.
  • Dual processor based with dedicated processor for high speed Serial or Ethernet connections
  • All signal in / out relays are isolated via DIN Mounted relay / terminal blocks
  • Elevator pre-signal contacts
  • Power quality metering
  • Elevator pre-signal

MX350 Controller Standard Equipment

Status LEDS for:

  • Source 1 and 2 Availablity
  • Source 1 and 2 Connected
  • Transfer Inhibit
  • Active Alarms
  • Time Delay Active

Graphical Display:

  • Color graphical display with USB Calibration/programming port and Embedded Help
  • Displays 256 time-tagged events with 1 ms resolution
  • Provided detailed outage,test,and diagnostic reports
  • Monitors over/under frequency, voltage conditions, frequency imbalance, and phase rotation

Ranges of Controls / Metering:

  • Neutral, Engine Start, and Engine stop time delay timers
  • Contacts for Source 1 and Source 2 position indication as well as remote load test signals, and engine start delay
  • Synchroscope
  • Programmable generator exerciser
  • Source 1 and Source 2 In-phase monitor

Testing and Certification

  • Tested in accordance with:
    IEC 60068-2-30
    IEC 60068-2-1
    IEC 60068-2-2
    IEC 60255-22-1
    IEC 60255-22-2
    IEC 60255-22-3
    IEC 60255-22-4
    IEC 60255-22-5
    IEC 60255-22-6
    IEC 60255-25
    IEC 60529; IP54 (front),IP20(back)
    IEC 61000-4-11
  • Conforms to EN 60947-1, EN 60947-6-1, EN 60255-26 (EN 50263), EN 5502 / CISPR22 / EN 61000-6-2 / EN 61000-6-4
  • Quality System:
    Manufactured under an ISO 9001 Registered Program

MX350 Controller Optional Equipment

Option Package A:

  • Full function ATS control with full sensing and control capabilities
  • Expanded diagnostics, high-speed 256 event capture, 365 days
  • Monitoring Software (local or remote), USB interface for uploading and downloading setup parameters
  • Four (4) programmable inputs and four (4) outputs assignable to additional ATS features
  • Full complement of programmable ATS control switches AUTO / MAN, Preferred Source selector,Commit / No Commit Xfer, Transition Mode Select for Closed Transition switch models)

Option Package B:

  • Includes Option Package A features, plus
  • Ten (10) customer programmable digital and ten (10)analog alarms.
  • Twenty (20) channel data logger, customer configurable sample period from one (1) cycle to sixty (60) minutes.
  • Waveform capture, ten (10) channels, up to 256 cycles each sixteen (16) samples / sec.
  • Auto Load Shed with voltage, frequency and kW triggers.

Option Package C:

  • Includes Option B features, plus
  • Four (4) additional inputs and outputs (totaling eight (8) in & eight (8) out)

Option Package D:

  • Includes Option Package C features, plus
  • Four (4) additional inputs and outputs (totaling twelve (12) in & twelve (12) out)
  • Customized user control logic

Option Package M:

  • Configuration for Manual Operation only (Non-Automatic)

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