On the Safe Side with the New K-System Safety Relays

Especially in safety-related applications, reliable emergency shutdown or activation is indispensable for protecting personnel and equipment. This is why our new safety relays have a 1oo3 (one out of three) structure, using triple redundant contacts. Compared to a single, force-guided contact, the 1oo3 structure offers the key advantage of higher availability. If the single contact of a force-guided relay fails, control of the field device will be lost. In a 1oo3 structure, one or even two contacts can fail without compromising operation of field devices. This, in combination with SIL 3 and ATEX approval for Zone 2, guarantees maximum reliability in your process plant.

With separate models for DTS (de-energized to safe) and ETS (energized to safe) applications, the new K-System safety relays are cost effective — you can choose the appropriate safety relay for your individual application and include only the needed functionality. Using the existing proof test inputs, the proof time interval for relay modules can be extended, as well. The new safety relays will be an asset in PFD (probability of failure on demand) budgeting, with their excellent proof times of 32 years for DTS and 10 years for ETS.

The K-System safety relays are 1-channel, loop powered, and feature test inputs for proof testing of all relay outputs. The input circuitry is identical for all devices: If one device is compatible with a control system DO (digital output) card, all other modules of the new safety relays are also compatible. Changes or adjustments to the input circuit can easily be applied to the entire product family.

• 1oo3 structure offers higher availability on demand compared to the single, force-guided contact
• DTS- (de-energized to safe) and ETS (energized to safe) version available, each with up to 5 A switching current (20 mm version) or up to 3 A switching current (12.5 mm version).
• Excellent proof times: 32 years for DTS, 10 years for ETS
• Test pulse immunity against a variety of ESD and DCS systems and high efficiency
• Inputs are compatible with DO cards used by many ESD and DCS systems