The Siren Board

The city I got mine from threw my blower out so I was thinking of getting a 1623 CFM shopvac thing with like 3 speeds and i don't want to blow the siren or something like that. I was thinking of starting at one of the lower speeds on the shopvac and loosely connecting it to a wide pipe thing and feeding that under the siren. If like I said I do that I don't want to damage the siren although it doesn't seem to me it would hurt it considering it's just air but that's why I am checking here.

a shop vac won't hurt it. that advertised "1623 cfm" is with almost no restriction on the inlet or outlet. most vacuum cleaner blowers are the "hamster wheel" type; they move a lot of air (unrestricted) but can't generate much pressure. Once you block a significant portion of the outlet (like trying to make it push air through a Thunderbolt head) it's cfm output will drop to nearly nothing.

the Roots blower that the siren originally used didn't move nearly as much air (roughly 250 cfm) but could generate 5-6 psi of pressure since the internal clearances of a Roots blower are very tight and air has no escape path.

Oh okay. Thanks a lot.

Yeah, shop vac ratings are very "optimistic". There is no way you can overpressurize a tbolt with a shop vac or leaf blower.

Oh okay. Like I said I thought I would check and make sure because I know the blower has safety release valves but I didn't think the siren head did. But it's good to know that a shopvac won't over do it. I must ask though is there a way to overpressurize it? (I am asking so I can avoid it.)

You have nothing to worry about. Your not going to overpressurize it.

coastalsyrolover wrote:Oh okay. Like I said I thought I would check and make sure because I know the blower has safety release valves but I didn't think the siren head did. But it's good to know that a shopvac won't over do it. I must ask though is there a way to overpressurize it? (I am asking so I can avoid it.)

you aren't going to do it w/o some serious equipment; either a larger/faster-operating Roots blower, or a sizable air compressor (and by sizable, I mean an industrial one.)

Just wondering, if you did put too much air into your tbolt what would happen .

I wonder what would happen if someone put a single phase motor on a 3 phase series A1 blower.

ENec wrote:I wonder what would happen if someone put a single phase motor on a 3 phase series A1 blower.

It would be a single phase A1 blower...