Istec SpeedSys 300

The SpeedSys 300 is a SIL 3 rated overspeed protection system for rotating machinery. It delivers the core layer of protection with a compact architecture. Its small technical footprint enables low-impact retrofitting and extends the range of machinery which can be protected.   

For SIL 2 applications visit the SpeedSys 200 page »

For non-SIL applications, check out the SpeedSys tachometer series »

Safety by design

The simple and robust design of the SpeedSys 300 meets the latest safety standards, and features easy maintenance and long proof-test intervals.

Any configuration

The overspeed protection system is compatible with all sensor types and applicable in any environment, making it easy to install and retrofit.

Reversed scalability

SpeedSys 300 is designed for SIL3 applications, but can be scaled back to any type of application, from multi-module voting structures to stand-alone configurations.

“The most advanced overspeed detection system for rotating machinery”

Design concept

SpeedSys 300 is designed as an independent layer of protection; to be fundamentally simple and robust. It delivers fast and reliable protection for speed and acceleration and complies to the industry standards.

A separate monitoring module can be added to include extensive monitoring and connectivity features to the configuration.


The system architecture is designed to suit a wide range of applications. A single module can offer a reliable and economical solution for overspeed protection. Redundancy and voting structures can be created for more demanding applications or increased availability. Typical applications include:

Hydro turbines
Compressors and pumps
■ Aeroderivative gas turbines
 Gas- and steam turbines
 Marine applications


Certified safety

SpeedSys 300 has been designed to meet the requirements for SIL 3 certified overspeed protection, featuring fast reaction times, long test intervals and sufficient safety outputs.

Advanced self-monitoring

The system includes a continuous data validation process, ensuring an accurate operation and proof-test intervals of 10 years.

Isolated inputs

Isolated inputs eliminate the need for separate isolators or barriers in the field, reducing failure modes and increasing sensor monitoring functions.


System features

  • SIL 3 certified protection
  • 8 ms system response time
  • 2 safety relays + 1 safety analog output
  • Suitable for Hall-effect-, electromagnetic- or proximity sensors
  • Automated proof-tests


  • ATEX/IECEx Zone 0,1,2 (Ex ia) isolated inputs
  • Advanced self-monitoring and diagnosis
  • 10 year proof-test interval (typical)
  • External voting for redundant configurations
  • Modbus


  • API 670
  • API 612
  • IEC 61508, SIL 3

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