Ensure Safe and Quick Synchronizing in Power Plant Applications

M-5625 Syncrocloser® Digital Synchronizing System

Get online with Beckwith Electric's Syncrocloser products: SyncCheck, automatic synchronizing and speed/voltage matching relays. They offer the best accuracy in the industry to assure safety for your most expensive asset.

M-5625 Integrated Synchronizing System® for Generator and Intertie Synchronizing

The M-5625 Syncrocloser® Digital Synchronizing System is suitable for the automatic synchronizing of a generator to the electric power network. The system provides speed and voltage "jogs" to bring a generator to proper conditions of matching voltage and frequency, prior to safely and accurately closing a breaker into a bus energized by an electric power network.

The Digital Synchronizing System is intended for three general classes of application:

  • Initial connection of a generator to a power network
  • Closure of a network breaker where there is a possibility of a split of the system into two isolated networks having different frequencies
  • Breaker closure applications with a static phase angle
  • Automatic Synchronizing
  • The system can also be used for manual synchronizing application.

Digital Synchronizing System

When the M-3410A relay is connected with Line-Line voltage input, the following functions are available (refer to the Specification for wiring connections).

  • SyncCheck with Phase Angle, DV and DF with dead line/dead bus options (25)
  • Reconnect enable (79) for intertie application
  • Phase undervoltage (27) detection
  • Dual-setpoint, single or three phase, directional power monitoring that can be selected as over power or under power (32) detection (requires current transformer input)
  • Negative sequence overvoltage (47) detection
  • Phase overcurrent (51) detection (requires current transformer input)
  • Phase overvoltage (59) detection
  • VT fuse-loss detection and blocking (60FL)
  • Four-step over/under frequency (81) detection

Your Benefits:

Ability to get on-line quickly

  • Unique proportional-pulse width-to-setpoint error algorithm takes into account the inertia lags in rotating machinery and control lags found in governor controls
  • Commissioning is made easy with large calibrated control knobs for all tunable parameters. (No need to scroll through menus while the system is being tuned)
  • Assure desirable power flows with the ability to select synchronize with VAr export and real power export on synchronizing

Enhanced security and operational use

  • Best accuracy in the industry
  • Ability to use "operator window" to supervise operator closure of generator breakers
  • Ability to use phase angle/slip frequency (versus phase angle/time) synch-check so close tolerance phase angle settings can be maintained - Phase angle/slip synch check can be used in generator or bus tie applications - Rack-mount and retrofit-style cases, including vertical mount

Generator Synchronizing

Smooth, efficient and safe synchronizing of generators, transfer of plant auxiliary motor buses or reclosing of transmission line breakers are the ultimate reasons for using equipment in the Syncrocloser Line. Each of the products has been carefully engineered to virtually eliminate the possibility of damage caused by faulty synchronizing.

Safeguard the Source!

The M-0193 Syncrocloser (Automatic Synchronizer) exhibits the best accuracy in the industry for advance closing angle prediction to lead to close at phase angle difference. If you don't think accuracy is important, did you know that a 12° phase angle difference can hard-load a machine with 30% of full-load shock? That is stress your machines should not endure! This is especially true for peaking machines that are synchronized daily, and large base-load machines that are built with tight tolerances.

Application Flexibility
The M-0193 Automatic Synchronizer can be multiplexed to different generators that have different breaker closing times. An infinite amount of different breaker closing times can be obtained by simple contact closures to the M-0193 relay.


In a world of menu-driven HMIs on relays, the M-0194 Speed and Voltage Matching Relay has simple and simultaneous access for all tunable parameters. The ability to have all parameters with easy-to-read, clearly-marked controls is a great asset to get the commissioning task performed properly and in a timely fashion.

Scalable Application

Based upon the importance of the generation asset, relays may be applied in series for greater security; synch-check relays can be used to back up an autosynchronizer or operator. Speed and voltage matching relays may be used with autosynchronizers for completely automated synchronizing sequences. Synch-check relays may also back up control systems with integrated synchronizing for improved security, and to provide a supervised manual synchronizing path.

Concise Speed Control

Using a unique proportional-pulse width-to-setpoint error algorithm, the M-0194 Speed and Voltage Matching Relay is able to cope with the inertial lags in rotating machinery and control lags found in governor systems. These lags, if not properly compensated for, cause the speed (frequency) of the machine undergoing the synchronization process to hunt excessively, resulting in long synchronization times, wasted fuel and possibly a generator trip on incomplete sequence timing. For peaking service, the proportional pulse width-to-setpoint error algorithm offers the fastest synchronizing times.