M-4272

Digital Motor Bus Transfer System For Low Voltage (LV) and Medium Voltage (MV) Switchgear Applications

Integrated Synchronizing System®


M-4272
  • Provides Automatic and Manual transfer of motor bus systems in power plants and industrial processing plants to ensure process continuity

  • High Speed Fast Transfer in 2 to 3 Cycles.

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

  • Applicable for one way and bi-directional Manual and Automatic transfers

  • Can be expanded to accommodate multiple breaker configurations

  • Multiple setpoint profiles for various application requirements

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

  • Extensive commissioning tools, including ringdown analysis

Standard Features

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

  • Sequential or Simultaneous Transfer Mode

  • Transfer initiated by protective relay external to the MBTS

  • Automatic Transfer after a loss of the motorbus supply voltage based on the programmable undervoltage element. This provides a selectable backup feature if a manual or protective relay transfer is not initiated.

  • Fast Transfer with adjustable phase angle limit

  • Sequential or Simultaneous mode for the Fast Transfer

  • 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 and In-Phase Transfer are not possible

  • Fixed Time Transfer after an adjustable time delay

  • Programmable Load Shedding with no time delay for Fast Transfer

  • Programmable load shedding prior to initiating in-Phase Transfer,Residual Voltage Transfer, and Fixed Time Transfer

  • Adjustable setpoints for delta voltage limit and delta frequency limit

  • 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 (Make-before-break)

  • Fast Transfer, In-Phase Transfer,or Residual Voltage Transfer (If the Hot Parallel Transfer is disabled)

  • Programmable Load Shedding with no time delay for Fast Transfer

  • Programmable load shedding prior to initiating In-Phase Transfer and 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-4272 devices

  • Breaker status supervision

  • Breaker failure monitoring

  • Four trip and close circuit monitoring inputs

Additional Standard Features

  • Bus Phase Undervoltage (27B)

  • Frequency (81) and Rate of Change of Frequency (81R) for load shedding

  • Breaker Failure (50BF), 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 lock-out/blocking output contact, and 11 programmable output contacts (10 Form 'a' and one Form 'c')

  • Six Breaker Status inputs (a, b, and service position) for the Source 1 and Source 2 breakers, twelve programmable digital inputs

  • All functions can be enabled or disabled

  • Remote/Local control selection

  • Device ON/OFF Control Selection

  • M-3972 Status Module

  • IRIG-B time synchronization

  • Oscillographic recording

  • Two RS-232 ports (front and rear) and one RS-485 port (rear)

  • M-3872 ISScom™ Communications and Oscillographic Analysis Software

Optional Features

 


Sales and Service