Slow 2t22 rise by wiring motor to 480V on 240V supply?

[Brendan Ahern]

For any kind of machinery I follow a very simple formula. If the manufacturer of said machinery does not say you can do something, then don't. I would not recommend doing anything to that siren that would make it operate differently then it was designed to. Thats just asking for trouble.

[Robert Gift]

What is the whole point of this? The 2t22 is beautiful sounding siren, are you trying to make it sound like a Carter or something?

Yes!
Somewhere on line I heard a 2t22 which had a slower more appealing rise than our 2t22A.
Ours rises to peak so quickly that it sounds overpowered.

The motor is connected to the 208-240 taps on 240 V line voltage.

(I tried to make a video recording, but as soon as it got loud, the JVC Hard Drive camcorder stopped recording and displayed an error message.)

If it would be as simple as changing three wires to 480 volt operation on 240 input, with no harm, I would try it.

[JasonC]

Robert, the best thing for you to do, is install the siren properly at the treatment plant with no modifications and run a phone wire to the fire station to a control.

Burying a separate three phase feed from the treatment plant will not only cost a lot, it will violate multiple NEC codes and your municipality (or Fire Marshall) will make you take it right back down. (that's IF you can find a licensed electrician to do it in the first place)

If you want a siren to play with, you need to get one for yourself. This siren is used for real warnings, so you shouldn't mess with it. Any siren enthusiast here that has put a siren back up in real service has done it properly as the manual says. You will burn the siren motor up if you don't do it properly. A siren that might not work is almost useless.

The only safe way to "slow" the siren's startup to your liking (even 208v wont slow it much) would be to buy a variable frequency drive. And I don't think you want to plunk down $1,500 for that. Just leave it be

[Robert Gift]

Yes. The NEC Codes is another problem.
But by making it a "temporary" plug-in connection, I can run three-phase to a building (fire station) which has single phase.
I must keep both systems separate and independent.

The problem with the sewage plant is that the siren is too low.
It would be very difficult to auger a hole, obtain and install an expensive pole and install the siren near the three-phase power meter.
I have dug plenty of trench by hand, so it will cost less to run wire to the station and place the siren on the roof.
I will do all the work myself to code. It will be inspected by the county building inspector.

[JasonC]

Yes. The NEC Codes is another problem.
But by making it a "temporary" plug-in connection, I can run three-phase to a building (fire station) which has single phase.
I must keep both systems separate and independent.

The problem with the sewage plant is that the siren is too low.
It would be very difficult to auger a hole, obtain and install an expensive pole and install the siren near the three-phase power meter.
I have dug plenty of trench by hand, so it will cost less to run wire to the station and place the siren on the roof.

A siren isn't a temporary connection. Neither is buried conduit or permanent structures. It will simply fail inspection.

Plopping up a telephone pole will be how much? $100-200 or so for a used pole? (many times power companies will donate and set up a pole for free) Running three cables several hundred feel of 8 AWG copper cable will run you how much? (100' is about $120 now). Not only that, the pole route will be the most legal.

[Robert Gift]

By installing a weatherproof box and weather-rated plug, I meet the NEC requirements to allow such a connection. We could unplug at the meter during winter months when a tornado is very unlikely.
But the monthy 1st Saturday Noon tests would continue.

My voltage drop calculations predict #6 AWG (I planned #4 AWG AL direct bury Triplex.)
I'll have to run an additional #8 bare CU ground on the triplex so that if someone digs into the buried cable, they will have a good ground to short to and trip breakers.

I considered the pole because it is a separate "structure" to which I can run three-phase.
But the 2t22 requires a class two pole and they are very expensive. I even considered cutting Lassie's former pole at ground.
Would yield a 45' pole. 38 feet after planting.

[JasonC]

I'm 99% sure NEC won't let you run a temporary type connection for a permanent structure (someone correct me otherwise, especially one fed by a separate service). And even if they did, they whole setup you have planned is extremely unorthodox. You also have to run two more wires for the thermal overload switch (BTW, burying a copper ground wire wont do much good since very little current leaks to ground across a delta connection, which is what I'm assuming the plant has, thus, no breakers will trip).

Telephone poles are expensive, but in your case, the easiest method of installation. Either that, or get the power company to upgrade the fire station to three phase (everything from the panel onwards will have to be replaced as well).

[Robert Gift]

You're correct. This is unorthodox.
The "temporary" three-phase circuit shut-off switch must be mounted next to the existing single-phase service meter/shutoff.

It would be too expensive to upgrade the station to three-phase.
Sadly, last year we just bought a single-phase cascade system to fill our SCBA tanks. We could have obtained a free three-phase system from the closing Rocky Mountainn Arsenal fire station.
I could have buried three-phase supplying the station and disconnected the existing single-phase service and not have this "two services" conflict.

Interestingly, that bare CU wire is not for leakage but to assure a quality ground to which to short if someone digs into the buried cable.

The thermal overload circuit would be connected to the motor starter switch, so it could run just from the siren to its motor starter switch. Right now I have the 120 VAC running from the manual siren activation switch (light switch) in the laboratory through the siren's internal thermal overload switches (P1,P2) to the starter switch. So if any thermal overload switches open, power to the siren ceases.

[pyramid head]

EDIT: I do not care, no point in trying to help, seems how some people shunt my words. Good luck Robert, have fun.

[Nelso90]

Dude, a model A versus a 2T22???
I personally think you should mount the 2T22 on a pole made of Inconel 718 with integrated resonant cavities, waterproof the whole thing, and mount it inside the digester, so the water can amplify the sound. Christ!