New GESTRA SIL-3 approved conventional low & high level limiter systems

The new face and name of the conventional technology:  SPECTORmodul

Like in the past 40 years GESTRA again is setting the standard for the safety equipment of steam and hot water boilers.

The NRG 16-50 & NRS 1-50 will replace the old system NRG 16-11 & NRS 1-7

The NRG 16-51 & NRS 1-51 will replace the old system NRG 16-12 & NRS 1-8

Note: The new electrodes and switches will be able to work together with the old type components,
but any combination with old type electrodes or switches will not be according SIL. 

 Which are the main reasons to replace the well introduced low level systems NRG 16-11 & NRS 1-7 // NRG 16-36 & NRS 1-9 // NRG 16-12 & NRS 1-8?

• In 2002 the PED and the related harmonised European Norms 12952/53 came in place. With the PED, GESTRA applied the European type approval to the safety systems NRS 1-7/8, which were designed back in 1989.
• The SIL requirement for safety limiting systems was published with the issue 12.2008 of the European Norm 12952/53 for the first time. This Norm requires at least a SIL 2 safety level for fired pressure vessels (steam and hot water boilers).
• The requirements for the Electro Magnetic Compatibility (EMC) where dramatically increased over the last years. Therefore different approval authorities already indicated to refuse the extension of the various approvals for the NRS 1-7/1-8.
• GESTRA not just fulfil the present regulations, but set the standard in terms of safety, operational function and maintenance with the new systems NRS 1-50 for Low level alarm & NRS 1-51 for high level alarm.

The new systems were consequently designed according to the IEC 61508 (Functional safety of electrical/electronic/programmable electronic safety-related systems). Also the production quality and the life cycle management have to be monitored, in order to fulfil the SIL 3 (Safety  Integrity Level) requirements.  SIL-3 level is reached by using a "one out of two" system (1oo2)

The new safety systems can be used for both, the land based installation (for LW and HW limiters) and also for the operation on ships (LW limiters only).

Further features:

• Front accessible and detachable terminals (Fast and easy installation and service)
• 24VDC +/- 20% power supply (Less variations, independence of local power supply voltage, able to integrate in battery backup safety power networks).
• 100-240 V +10/-15%, 47-63 Hz versions also available.
• Strong variation reduction through high flexibility of the basic design.
• Detailed failure diagnostic, displayed with three separate LED's.
• Reduced installation effort and investment cost by using only one amplifier NRS 1-50 in combination with two sensors NRG 16-50.
• Variable use of the safety related output contacts. With this option it’s possible to respond to different international boiler equipment regulations.
• Two separate, independent output contacts to monitor both alarm channels.
• Modified and optimised sensor design, now installation in standard flange versions possible.

Download INFO PDF (English)

Download INFO PDF (Nederlands)

For additional information please get in contact with:
ing. Fons de Jong  - Product Manager Gestra boiler-electronics
Telephone: 0182-642 269  /  Fax: 0182-642 233
Email: fons.dejong@mrctransmark.com