The Siren Board

I have heard of rotary converters for converting single phase power to three phase power, but will a simple transformer do the trick. If so, how?

Nope

That's not going to work. Ideally you will need a rotary phase converter.

Now the other thing you need to know about it is that you will need a CNC rated phase converter, or a double size RPC to start a siren.
What that means is that if you have a 10 h p motor on your siren you will need s 20 hp motor on the phase converter to start it. Reason is that the motor is going to be under a high load
when you spin it up. The typical use for a phase converter is for 3 phase metal working machines that don't present a high starting load. Sirens have a high inertial load. You are starting a heavy rotor that fights being spun up.

Now another option is a VFD (variable Frequency Drive) these will take single phase and make 3 phase as well and offer things like soft start. Be aware that any sort of soft start will make the siren not spin up at the same rate as a standard 3 phase power supply so the purists may not find it workable because the inital rise of the siren will be altered.

As far as rotary phase converter design and building. There is a ton of info on the web about doing it. And as I mentioned before, you will want a CNC rated unit. That is going to be a design that has run capacitors from leg A to leg B and from leg B to leg C. Typical designs only run from leg A to leg C. For heavy start applications this will not work.
My advice is that if you have some electrical knowledge, build one. To buy a unit that will start a 10 HP siren, you are looking at over 1200 bucks for the RPC.

Allertor125guy wrote: ↑

Sat Jun 15, 2019 8:57 pm

I have heard of rotary converters for converting single phase power to three phase power, but will a simple transformer do the trick. If so, how?

Would this be helpful? https://www.airraidsirens.net/proj_3phase.html