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For more than 60 years, GfG has been committed to protecting people, industrial facilities and the environment by developing and manufacturing gas detection systems. With an extensive range of portable gas detectors and fixed gas detection systems, GfG can supply you with a selection of products for many applications and industries. Our scope also includes on-site service and advanced training courses.


What distinguishes us from other manufacturers

We are specialists for gas detection solutions, not generalists in safety. No one can be the best at everything, but if you focus on one thing, you can achieve excellence. We work hard to provide you with the best gas detection equipment available, so you can focus on your task without having to worry about the risks that gases can pose. Because of that we invest more heavily in research and development than any other company. Approximately 13% of our annual turnover is reinvested in basic research and the development of new sensors and devices.


A “never say no” approach

This includes finding solutions for customers whose requirements are not met by “off the shelf” products. We take pride in our longstanding cooperation with the Singapore Civil Defence Force (SCDF), for example. For many years now, they have put their trust in GfG’s portable devices, which we optimized to adapt to the Singaporean climate and fulfill the special requirements for integration into the SCDF communication network.

GfG controllers and certain transmitters have internal relays. External alarm devices such as information signs, warning lights and signal horns can thus be directly connected and managed. The same applies to measurement-controlled ventilation systems and valves. Complex gas warning systems, however, require a large number of automatic safety measures that are initiated when the defined gas limit values are exceeded or undershot. Up to four relay modules GMA200-RT can be connected to the GfG controllers via the RS-485 interface. The total number of relays per gas detection computer can thus be increased by up to 64.

Extension of safety functions
The GMA200-RT is equipped with 16 relays, each with a potential-free changeover contact. In addition to 16 external alarm devices or other measurement-controlled devices and functions, an external pushbutton can also be connected for alarm acknowledgement. Due to the spatial separation of controller and relay module, safety measures in remote areas (up to 1,200 m) can be implemented with significantly less cabling effort. The operating voltage of the GMA200-RT is 24 V DC. Power supply is also possible redundantly via two power supplies. The device is configured via a gas measuring computer (using GMA200Config software) or via the mini-USB socket (USB type B) using a PC.

Indicators and Functional Safety
For each relay, an LED on the front of the relay module lights up to indicate operation and any alarms or faults in color. In addition, four status LEDs indicate the operating status as well as service and error messages. The hardware of the GMA200-RT meets the requirements of functional safety according to DIN EN 50402. In single-channel use (1oo1), the SIL capability corresponds to 2, in redundant use (1oo2) to 3.


Key features at a glance:

Generall information:

  • Suitable for the GMA200 and GMA22 gas detection computers
  • 16 relays with one potential-free change-over contact each with status display
  • Connection via RS-485 interface (Modbus)
  • Connection of up to 4 relay modules per controller
  • Top-hat rail mounting (TS35)
  • Configuration via software GMA200Config with gas measuring computer and PC

Approvals / Certifications:

  • SIL level 2/3 (depending on contact load of relay switching output)

Would you like to know more?

Our team can help you with any product information, quotes, or any general questions you may have about the product.

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