Anybody recognize this FS&S STH-10B?

[Tboltguy]

Greetings all,

I recently acquired this FS&S STH-10B, and I'm currently trying to figure out where it was originally installed. If anyone recognizes my siren or has any ideas, please let me know!

Thanks, Milo

[Reactor Cat]

Idk but from what i see, Its a 1 phase

[championsiren]

Idk but from what i see, Its a 1 phase

He... already knows that. He literally said so in the title, hence the name of the thread being "Anybody recognize this FS&S STH-10B?" Why would you make that comment? It doesn't provide any useful info or help the author.

Anyway, back on topic.
Your siren is very strange. It looks like an early (late 50s-early 60s) three-phase model, but the tag says it's single-phase. It has a GE motor which is usually three-phase (every GE motor STX-10 and XT22 I've seen is three-phase).
STH-10Bs usually look like this.

[Reactor Cat]

Idk but from what i see, Its a 1 phase

He... already knows that. He literally said so in the title, hence the name of the thread being "Anybody recognize this FS&S STH-10B?" Why would you make that comment? It doesn't provide any useful info or help the author.

Dont have to be rude about it. Im not that familiar with FS sirens

[championsiren]

Idk but from what i see, Its a 1 phase

He... already knows that. He literally said so in the title, hence the name of the thread being "Anybody recognize this FS&S STH-10B?" Why would you make that comment? It doesn't provide any useful info or help the author.

Dont have to be rude about it. Im not that familiar with FS sirens

Oh, sorry.
Well, Three-Phase sirens have an A at the end of the name (ex: 3T22A) and Single-phase sirens have a B at the end of the name (ex: 3T22B)

[Tboltguy]

Idk but from what i see, Its a 1 phase

He... already knows that. He literally said so in the title, hence the name of the thread being "Anybody recognize this FS&S STH-10B?" Why would you make that comment? It doesn't provide any useful info or help the author.

Anyway, back on topic.
Your siren is very strange. It looks like an early (late 50s-early 60s) three-phase model, but the tag says it's single-phase. It has a GE motor which is usually three-phase (every GE motor STX-10 and XT22 I've seen is three-phase).
STH-10Bs usually look like this.

I can confirm it's a single phase, it has four brushes at the bottom of the motor and two wires coming from the motor. I wired it up the other day, and the motor just buzzed. Currently working on troubleshooting that.

[Model L]

I can confirm it's a single phase, it has four brushes at the bottom of the motor and two wires coming from the motor. I wired it up the other day, and the motor just buzzed. Currently working on troubleshooting that.

does the rotor spin freely by hand? it should.

[Tboltguy]

I can confirm it's a single phase, it has four brushes at the bottom of the motor and two wires coming from the motor. I wired it up the other day, and the motor just buzzed. Currently working on troubleshooting that.

does the rotor spin freely by hand? it should.

It does, but the bearing isn't great. Hoping to get the motor cap off and lubricate it tomorrow.

[OHIO Desperado]

If it's just buzzing I would be looking at the brushes.
Those motors are a repulsion / induction design. The brushes are actually shorted together and the field induces currents into the armature creating the magnetic field.

A common failure on them is the brushes get locked up in the holders and stop making contact with the commutator rendering the siren inoperable.

www.carbonbrushes.com has the brushes for that siren for FAR less than what federal wants for them. They are also a common brush size. They were used by Lincoln Electric in the 200 SA engine driven welders in the exciters.

Measure the height width and length of the brushes and use that info to get the right ones. I believe mine were 30 bucks of something to that effect, but they were not real expensive. You will no doubt need to pull the brush holders and clean them out real good and possibly use a file to open them up enough for the brushes to slide smoothly in and out. Springs can be rebend if the tabs are broken off.

To seat the new brushes, use the directions from federal included in the STH / STL-10 manual located here on the site.

I would advise using 110 volts to run in the brushes however. It will need to be run for a length of time and dealing with a tornado siren at full song for that length of time only upsets people.

[Tboltguy]

If it's just buzzing I would be looking at the brushes.
Those motors are a repulsion / induction design. The brushes are actually shorted together and the field induces currents into the armature creating the magnetic field.

A common failure on them is the brushes get locked up in the holders and stop making contact with the commutator rendering the siren inoperable.

www.carbonbrushes.com has the brushes for that siren for FAR less than what federal wants for them. They are also a common brush size. They were used by Lincoln Electric in the 200 SA engine driven welders in the exciters.

Measure the height width and length of the brushes and use that info to get the right ones. I believe mine were 30 bucks of something to that effect, but they were not real expensive. You will no doubt need to pull the brush holders and clean them out real good and possibly use a file to open them up enough for the brushes to slide smoothly in and out. Springs can be rebend if the tabs are broken off.

To seat the new brushes, use the directions from federal included in the STH / STL-10 manual located here on the site.

I would advise using 110 volts to run in the brushes however. It will need to be run for a length of time and dealing with a tornado siren at full song for that length of time only upsets people.

Thanks for the help! I'll definitely take a closer look at the brushes and replace them if necessary. Only issue is they're held in by a small, highly tensioned spool of flat sheet metal, that I was advised would break or shoot out of the motor at unimaginable speeds if I tampered with it/tried to service it. Any advice for how to safely remove that without causing any damage?