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Looking for a controller for Darley STH-10B
Posted: Mon Jan 09, 2023 6:30 am
by Rampage98
I recently rescued a 1960 Darley siren from our local fire hall from going to the dump. The fire hall has been out of commission for decades & the controller is long gone. I would like to restore it in working order & donate it back to our new hall. I got a hold of Tom Darley & he seemed to think Federal Signal made the motor in 1959 and to check with them for a controller. Been talking to tech support at Federal & they don't have anything to run the 10hp, 220V, 1 phase, 60 Amp. So looking to build my own. Trying to find a soft starter & getting no where with that. Does anyone have any ideas i can research on? Thanks.
Re: Looking for a controller for Darley STH-10B
Posted: Mon Jan 09, 2023 6:43 am
by Synther
Great find, what you have is a Federal Signal STH-10, redesigned and sold under Darley. It can be controlled fairly easily, all you need is a motor starter (Federal Signal RC5 or equivalent), which can be ran with a timer of your choice. You can try sourcing a timer on here, a good start is to look for a Federal Signal AR. There is a wiring diagram that should help you on page 17.
http://www.civildefensemuseum.com/siren ... 5A154F.pdf
Re: Looking for a controller for Darley STH-10B
Posted: Mon Jan 09, 2023 7:01 am
by Rampage98
Awesome!!! Thank you sir. Quick question, has anyone ever tried a VFD to run these? That was another option but quite pricey. Thanks.
Re: Looking for a controller for Darley STH-10B
Posted: Mon Jan 09, 2023 7:18 am
by Synther
These motors are induction/repulsion, so a VFD isn't compatible. Fortunately these motors don't demand a ton of power.
Re: Looking for a controller for Darley STH-10B
Posted: Mon Jan 09, 2023 4:06 pm
by jerrylovessirens
I just wanted to come in and say nice save! It looks to be in really good shape. Do a bearing check, sandblast and repaint the shroud, and it should be good for another half century!
Re: Looking for a controller for Darley STH-10B
Posted: Tue Jan 10, 2023 6:49 pm
by Rampage98
Thank you for the replies guys. So it looks like i'll be building my own controller. The biggest challenge i'm finding is finding a soft starter that is rated for 60 amps & single phase. Siemens, Schneider, Allen-Bradley, etc don't make any for those specs but i might have found one made by Carlo Gavazzi. I need to read the spec sheet to be sure and they are 29 weeks out for back order. I questioned tech support at Federal about the 60 amps and suggested that was start up current & he said no, they will pull 50+ amps when running... I'm welcome to any more ideas and i'll post updates of success for anyone else planning on building their own. Thanks again guys!
https://www.alliedelec.com/product/carl ... /70807962/
Synther: My reply back from Federal tech support is that they quit making the RC5 decades ago.
Re: Looking for a controller for Darley STH-10B
Posted: Tue Jan 10, 2023 7:44 pm
by Tyler
Rampage98 wrote: ↑Tue Jan 10, 2023 6:49 pm
Thank you for the replies guys. So it looks like i'll be building my own controller. The biggest challenge i'm finding is finding a soft starter that is rated for 60 amps & single phase. Siemens, Schneider, Allen-Bradley, etc don't make any for those specs but i might have found one made by Carlo Gavazzi. I need to read the spec sheet to be sure and they are 29 weeks out for back order. I questioned tech support at Federal about the 60 amps and suggested that was start up current & he said no, they will pull 50+ amps when running... I'm welcome to any more ideas and i'll post updates of success for anyone else planning on building their own. Thanks again guys!
https://www.alliedelec.com/product/carl ... /70807962/
Synther: My reply back from Federal tech support is that they quit making the RC5 decades ago.
You definitely need to get in touch with someone that's well versed in the field. Play guessing games and you'll have quite a rough time.
Re: Looking for a controller for Darley STH-10B
Posted: Tue Jan 10, 2023 11:11 pm
by Non-Zero
You may want to make a post on the actual Facebook Siren Group, there is more than what meets the eye going into this, and while I have had some success with past ventures such as this, if you do not know what you are doing you will screw up your stuff, or screw up how your left arm feels for a few hours.
Re: Looking for a controller for Darley STH-10B
Posted: Wed Jan 11, 2023 8:10 am
by Rampage98
Thanks for the reply guys. Just so you know what i'm capable of, i'm a retired electronics computer tech with 31 yrs at the Boeing Co in Seattle working robotics & cnc machines in equipment maintenance. I have returned home to my small town in Columbia Falls, Montana to have fun, and as you can guess it, restoring our local fire dept's hall siren as my first hobby project. I will get this going & i appreciate all the comments and the info from everyone. Cheers!
Re: Looking for a controller for Darley STH-10B
Posted: Wed Jan 11, 2023 4:01 pm
by Non-Zero
Rampage98 wrote: ↑Wed Jan 11, 2023 8:10 am
Thanks for the reply guys. Just so you know what i'm capable of, i'm a retired electronics computer tech with 31 yrs at the Boeing Co in Seattle working robotics & cnc machines in equipment maintenance. I have returned home to my small town in Columbia Falls, Montana to have fun, and as you can guess it, restoring our local fire dept's hall siren as my first hobby project. I will get this going & i appreciate all the comments and the info from everyone. Cheers!
That makes me feel a lot better giving this advice... You will want to find a 60A Dual Pole contactor rated for 240V, and the coil voltage to close the contactor will want to be a 120V contact, unless you have a control system capable of handling 240V as a control circut. As you have some experience, I would recommend attempting to locate an AR timer, but they are occasionally hard to come by. As the controls are entirely gone, I recommend either hooking up an Arduino to a Relay board that has a coil rated for 5V and is Normally Open, and is capable of switching 120v. Then it is a matter of hooking 120v into the relay, and in series with the coil on the contactor. Then you will want to find a 60A 240 service, wire it thru the contactor making the contactor in series with the 240V circuit. It should be pretty easy to make a script that closes the relay for 180 seconds (standard 3 min operation) for steady, and it is a little more intuitive to make a wailing signal. You may also want to look into getting the motor rebuilt with fresh bearings and a turned commutator to ensure full motor health. Good luck with this venture!