TCL | Overspeed Protection

Overspeed Protection

Electronic overspeed protection systems to replace old analogue electronic or mechanical devices. Systems can be SIL 3 according to IEC 61508.

Mechanical and older analogue overspeed trip systems are prone to:

  • Drift of the setpoint resulting in inconsistent operation.
  • The turbine has to run in order to test them.
  • Hard to maintain and scarcity of spares.

Microprocessor based overspeed systems offer the following advantages:

  • Can be tested whilst the turbine is shutdown.
  • Operating setpoint is constant.
  • Improved diagnostics.

The scope of supply may include:

  • Panel mounted monitor with test signal injector.
  • Magnetic or eddy current type speed probes.
  • Signal cabling.
  • Installation design.
  • Setup and testing of the complete system.
Probes Installed on PT Casing
Overspeed Probes

Istec SpeedSys 200

The SpeedSys 200 is a SIL-rated overspeed detection system for rotating machinery. It delivers a robust layer of protection with a compact footprint. Its small robust design and low-impact installation enables advanced protection in a wide range of machinery.

Safe by design

The SpeedSys 200 is built with safety in the design rather than the conventional method of proven in use.
‘Proven in use’ requires years of usage data. Changes to the device will invalidate this data and the certification. ‘Safe by design’ allows for easy recertification after changes.


The module is designed for a wide range of applications. A single module can offer an economical and reliable solution for overspeed protection. Redundancy and voting structures can be created for more demanding applications or increased availability.

Typical applications include:

  • Micro turbines
  • Wind turbines
  • Compressors and pumps
  • Aeroderivative gas turbines
  • Gas and steam turbines
  • Marine applications

Learn More »

Istec SpeedSys 200