M-4172

Digital Motor Bus Transfer System For Low Voltage (LV) Switchgear Applications
Integrated Synchronizing System®

 

 

  • The M-4172 Digital Motor Bus Transfer System provides automatic and manual transfers of motor bus systems on low voltage switchgears in power plants, industrial processing plants, and petrochemical facilities to ensure process continuity.

  • Engineered with the same performance under the hood as our purpose-built M-4272 Motor Bus Transfer System.

  • Automatically selects Fast, In-Phase, Residual Voltage, and Fixed Time motor bus transfers, based on varying system conditions.

  • Superfast and accurate decisions due to quarter cycle response with the ability to cope with highly dynamic conditions during transfer.

  • Integrated control, supervisory functions, sequence of events, and oscillograph recording in one device.

 


The M‑4172 Digital Motor Bus Transfer System features and benefits:

  • Supports Fast and In-Phase Synchronous Transfer Methods, as well as Hot Parallel, Residual and Time Delayed Transfers

  • Applicable for One Way and Bi-directional Automatic and Manual Transfers

  • Meets and Exceeds Industry Test Protocols and Applicable IEEE and IEC Environmental Tests

  • Integrated control, supervisory functions, sequence of events, and oscillograph recording in one device

  • 6 Inputs:
    • 2 Dedicated Inputs for S1 and S2 Breaker Status Contacts: 52a or 52b
    • 4 Programmable Inputs
  • 8 Outputs:
    • 5 Dedicated Outputs: Trip & Close S1 breaker, Trip & Close S2 breaker, Lockout/Blocking Alarm
    • 3 Programmable Outputs
  • Includes M-3871 ISScom Communications Software offering simplified settings, easy and panoramic situational viewing and concise event analysis tools

  • Design Backed by 37 Years of Proven Field Experience

  • Legendary Application Engineering Support by Seasoned Experts



Standard Features

Automatic Transfer:
The digital Motor Bus Transfer System (MBTS) provides the following Automatic Transfer logic and features:

  • Transfer initiated by protective relay external to the MBTS
  • Automatic Transfer after a loss of the motor bus supply voltage based on the programmable undervoltage element. This provides a selectable backup feature if a protective relay transfer is not initiated.
  • Fast Transfer with adjustable phase angle limit, delta voltage limit and delta frequency limit
  • In-Phase Transfer at the first phase coincidence if Fast Transfer is not possible.
  • Residual Voltage Transfer at an adjustable low residual voltage limit if Fast Transfer is not possible
  • Fixed Time Transfer after an adjustable time delay
  • Programmable load shedding prior to initiating In‑Phase Residual Voltage Transfer and Fixed Time Transfer
  • Verify the new source (the source to which the bus is being transferred) is healthy and within acceptable upper and lower voltage limits

Manual Transfer:
When a Manual Transfer is initiated the digital MBTS provides the following:

  • Sync check functions with adjustable parameters
  • Hot Parallel Transfer if enabled (makebefore- break)
  • Fast Transfer, In-Phase Transfer and Residual Voltage Transfer (if the Hot Parallel Transfer is disabled)
  • Programmable load shedding prior to initiating Residual Voltage Transfer
  • Verify the new source (the source to which the bus is being transferred) is healthy and within acceptable upper and lower voltage limits

Circuit Breaker Control:
The digital Motor Bus Transfer System includes the following Circuit Breaker Control features:

  • Control of two circuit breakers with two individual programmable breaker closing times
  • Three-breaker configuration can be provided by two M‑4172 devices
  • Breaker status supervision
  • Breaker failure monitoring

 


Additional Standard Features

  • Sequential or Simultaneous Transfer Mode
  • Bus Phase Undervoltage (27B)
  • Frequency (81) and Rate of Change of Frequency (81R) for load shedding
  • Breaker Failure Source 1 and Source 2
  • Bus VT Fuse-Loss Detection (60FL)
  • Auto Trip
  • Auto Close
  • Four dry output contacts (two trip and two close) for Source 1 and Source 2, one lockout/blocking output contact, and 3 programmable output contacts (2 Form 'a' and one Form 'c')
  • Two Breaker Status 52b (or 52a) inputs for the Source 1 and Source 2 breakers, four programmable digital inputs
  • All functions can be enabled or disabled
  • Remote/Local control selection
  • Device ON/OFF Control Selection
  • M-3931 Human-Machine Interface (HMI) Module
  • M-3976 Status Module
  • IRIG-B time synchronization
  • Oscillographic recording
  • Two RS-232 ports (front and rear) and one RS-485 port (rear)
  • M-3871 ISScom® Communications and Oscillographic Analysis Software

 


Optional Features

  • RJ45 Ethernet Port utilizing MODBUS over TCP/IP Protocol or IEC 61850 Protocol
  • 5 A or 1 A models available
  • 60 Hz or 50 Hz models available
  • Available in vertical panel mount
  • Redundant Power Supply
  • External TCM and CCM available

 


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