Functional Devices Announces Improvements to their Air Handling Unit Fan Safety Alarm Circuits

NewRIBOur AHU Fan Safety Alarm Circuits feature a 24 Vac/dc power input, one master relay, and a choice of either six (RIBMNLB-6NO), four (RIBMNLB-4NO), or two (RIBMNLB-2NO) alarm circuits. Below is a list of new features and their benefits:


* The bypass switch moved from the coil of the alarm input relays to the relay’s N/O contact controlling the master relay.
* If an alarm input relay is bypassed, the coil is not continually energized.
* If an alarm input relay should fail, it can be bypassed and the alarm input moved to a spare relay.
* The status output contact of an alarm input relay changed from N/C to N/O.
* This provides a fail safe signal to the control panel. The control panel will know if a safety trips or if a wiring circuit is open.
* The main output contacts (from the master relay) changed to two independent N/O contacts. Through the use of board mounted jumpers, the output terminals for these independent N/O contacts can be made wet or dry.
* Both supply and return fan VFDs can be controlled without the use of additional relays.
* Fixed terminal connections have been replaced with removable terminal connections.
* Easy termination
* Input safeties and status outputs can easily be moved from one alarm input relay to a different alarm input relay, if needed.
* Removable terminals provide better conductor isolation from other board components, greatly reducing the possibility of accidental shorts during the termination process.

For further information, fill out this short form, and you will be directed to a PDF download link.


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