Firelite MS-5UD Relays

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I have a Firelite MS-5UD that is being used for enthusiast purposes. I was wondering what the maximum voltage the relays can support before, well, blowing out. Reason is that I wanted to unorthodoxly wire a 120V~ Exit Sign to an alarm relay (Positive being untouched), and remove the battery to the exit sign; so that in an alarm the sign would activate. Definitely not up to NFPA code, but for me it would work.


When life gives you lemons....
Use 'em to build a battery powerful enough to power an FACP
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According to the drawing in the MS-5 installation manual the relays are rated for 30 volts maximum. My suggestion is to isolate the 120 VAC circuit using a relay like a PAM-1, -2, or -3. Switch 24 VDC from the panel output through a panel relay to operate the PAM relay.

PAM relays are available from a number of sources. ... -52068.pdf
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