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Can 24VDC from a remote fire alarm power supply, that is not UUKL listed for smoke control, serve as an input to start a smoke control exhaust fan?

Question asked by sjacobs on Apr 11, 2019
Latest reply on Apr 22, 2019 by sjacobs

I am trying to work through design issues with a smoke control system which is under construction at the moment. There are three smoke control zones with multiple smoke evacuation fans and associated soft starters. The soft starters require a 24VDC input to initiate the fan start. The design shows the 24VDC input originating from the smoke control panel (from an automatic or manual activation) via the fire alarm control panel’s auxiliary 24VDC power out. The fire alarm control panel, the smoke control panel and the fan are UUKL listed for smoke control, the soft starters are not. The fan controllers are physically too far away from the smoke control panel for this circuit to operate as designed. My question is can I pick up 24VDC from remote fire alarm power supplies, switch it through an addressable control relay for fan start?

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