MX350 Controller

MX350 Controller

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.

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Technical Summary

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

Controller Specifications

Source Sensing
120 - 690 VAC +/- 1% of nominal voltage (+/- .05 Hz, +/-.5 A)
Control Power
120 VAC
Communications Interface (optional)
Serial RS-485 upt to 115.2 Kbps or TCP/IP (10/100 base-T)
Undervoltage dropout for source 1 and source 2
75-99% of nominal
Undervoltage restore for source 1 and source 2
85-100% of nominal
Underfrequency dropout for source 1 and source 2
45 - 59.9 Hz
Underfrequency restore for source 1 and source 2
45 - 59.5 Hz
Overvoltage dropout for source 1 and source 2
105 - 110% of nominal
Overvoltage restore for source 1 and source 2
103 - 108% of nominal
Overfrequency dropout for source 1 and source 2
50.1 - 63 Hz
Overfrequency restore for source 1 and source 2
50 - 62.9 Hz
Voltage unbalance on dropout for source 1 and source 2
5 to 20% of nominal
Voltage unbalance for restore for source 1 and source 2
4 to 19% of nominal
Load control relay contacts
rated for 10A @ 24VDC or 120VAC
Load control relay contacts
0-259 minutes
Delay for engine cool down (U)
0-60 minutes
Delay transfer to nonpreferred source (W)
0-5 minutes
Delay NeutralTransition time delays (DT,DW)
0-10 minutes
Storage temperature
(-40˚C - 90˚C )
Operating temperature (ambient)
(-20˚C to 50˚C)

Standard Equipment

  • The Cat MX350 Controller for the CTE Series ATS
  • 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

Optional Equipment

  • MX350 Option Packages
  • 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)