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MainsPro G99TT

G99 Type Tested Mains Decoupling Relay
Order code: MP1G99TTAAB
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Product description

MainsPro G99TT is a protection relay for parallel-to-mains applications, including generator sets, cogeneration units, micro turbines or renewable energy sources such as photovoltaic plants or wind turbines. It provides adjustable voltage, frequency and loss of mains protections to safeguard both the distribution network and the generators.

The G99 functions were added as a result of UK adopting EU Commission Regulation on harmonising network standards known as Requirements for Generators (RfG) into GB Distribution and Grid Codes. The main change is that Vector shift has become forbidden means of Loss of Mains detection and the only approved method is now ROCOF.

The unit, being Type Tested device, has protection settings set during the manufacturing process. Some are hardcoded and cannot be changed and some of them are locked in a way that only authorized personnel can change them.

Key features

  • Full ENA EREC G99 Type Tested compliance
  • Required for all new installations in the UK from 27 April 2019
  • Wide power supply and measurement range 
  • Friendly interface with easy setting (no SW tools needed)
  • Simple wiring with detachable connectors
  • Remote binary communication
  • Suitable for standard DIN rail installation
  • Advanced frequency, voltage and loss of mains protections
  • History track (last 5 events)
  • Integrated mechanical lock to secure your setting
  • Breaker failure protection and watchdog 
  • Resistance to frequency jumps
  • Compliance with IEC 60255, G98, G99, IEn NR 005/2012 and VDE-AR-N 4105

Benefit-Compliant with Grid Protection Standards
Compliant with Grid Protection Standards Use one device all over the world, no matter where your project ends up
Reliability Manufactured in Europe, in compliance with industrial standards
Benefit-Easy to Use
Easy to Use Easy controllers installation and operation

Recommended by our customers

“TEDOM has been using ComAp mains decoupling relays for over 10 years – installing over 1500 units during this time on both new projects and upgrading older installations. MainsPro was first used immediately after the product release as a replacement for the NPU protection unit that we used before. Typical uses for MainsPro include switchboards of cogeneration units and gen-sets operating in parallel with the public distribution network. MainsPro accurately measures and evaluates the essential mains parameters, and provides reliable mains-decoupling protection. It also brings added benefits including excellent usability, possibility of mechanical sealing, a wider range of features and the ability to switch two-set settings via an external contact”

Petr Sedlák Electrical Department Manager


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