Synchronized phasors (synchrophasors) provide a real-time measurement of electrical quantities from across the power system. Applications include wide-area control, system model validation, determining stability margins, maximizing stable system loading, islanding detection, system-wide disturbance recording, and visualization of dynamic system response. The basic system building blocks are GPS satellite-synchronized clocks, phasor measurement units (PMUs), a phasor data concentrator (PDC), communications equipment, and visualization software.

Why Choose SEL?

  • SEL has a comprehensive portfolio of products to create a complete solution that meets your needs.

  • SEL has experience implementing systems worldwide and guarantees products with a ten-year warranty.
  • SEL relays and meters include PMU capability free of charge. This makes SEL systems economical and easy to implement.
  • The SEL Engineering Services team can design, install, and commission your system to meet your schedule and budget.

Learn how a U.S. utility worked with SEL to develop advanced software that leverages synchrophasor data to enhance real-time grid operations.

See Live Synchrophasors and Try the Software on Demand

SEL is streaming synchrophasor measurements from wall outlets across the United States to a demo version of Synchrowave Operations. With your mySEL account, you can easily log in to this demo software to visualize live data and try out key features of Synchrowave Operations. 

System Components

Synchrophasors are currently being used by utilities around the world for system model validation, situational awareness, stability analysis, islanding detection, disturbance analysis, and wide-area measurement and control. SEL offers a wide variety of solutions to fit your application. Whether you are working with individual units or a complete system, SEL can help you design, install, and commission your system.


 Format  Synchrophasor Data Elements
PMUIEEE C37.118IEEE C37.118 Compliance LevelSEL Fast MessageMessage RateCT InputsPT InputsAnalogsDigitals
SEL-2240 Axion—Modular PMU2011 compliantP and M class1–60 mps64#64#64#30

and SEL-351S Protection Systems
11–60 mps33016
SEL-351RS Kestrel Single-Phase Recloser Control1 1–60 mps11016
SEL-421, and

SEL-451 Protection, Automation, and Control Systems;
SEL-411L Advanced Line Differential Protection, Automation, and Control System
11–60 mps661664
SEL-487E Transformer Protection Relay11–60 mps1861664
SEL-651R-2 Recloser Control1 1–60 mps36064
SEL-751 Feeder Protection Relay1 1–60 mps33416
SEL-751A Feeder Protection Relay01 1–10 mps33416
SEL-700G Generator Protection Relay1 1–60 mps66416
SEL-787 Transformer Protection Relay01 1–10 mps63416
SEL-787-3E/-3S/-4X Transformer Protection Relay*1 1–60 mps124416
SEL-311A, SEL-311B,

SEL-311L, and Legacy SEL-351 Relays
  1 mpm–1 mps33  
SEL-734 Revenue Meter 011–20 mps33  
SEL-735 Power Quality and Revenue Meter2011 compliantP class1–60 mps33416
SEL-2431 Voltage Regulator Control1 1–60 mps1208
SEL-400G Advanced Generator Protection System2011 CompliantP ClassYes1 -60 mps1861664

1 Level 1 compliant for TVE and frequency range.
# A maximum of 64 CT, PT, or analog inputs allowed.
*12 CT inputs and the 4 PT inputs are maximum for each and a unit can not be configured with both of these maximums.

IEEE C37.118-2011 defines performance classes P and M. IEEE C37.118-2005 defines performance classes 0 and 1.

Questions? Contact Us!

If you have any questions about SEL products, services, solutions, or support, please contact us. Our service and support professionals are ready to provide the answers you need.

Unbeatable Support

SEL support teams are stationed in regional offices around the world and staffed with application engineers who are experts in our products and in power system applications.

Technical support for SEL-manufactured devices is always free. No matter how often you need to call or how long your SEL products have been in service, you’ll reach an SEL expert who can provide the service and support you need.

Our cybersecurity team is always ready with the information and resources needed to keep your OT networks and critical systems secure and working effectively. Cyber services support contracts can include incident response, audits, system hardening, and more, depending on your anticipated needs.

More about SEL warranty and support