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JimmyS
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Discussion Starter · #1 ·
I'm a GC, and my electrician's supply house is stumped. My customer has an outbuilding we built about 5 yrs ago. Main electric load was a steam shower, plus lights and gas boiler, etc. They added a hot tub, which pushed the subpanel to the limit of its breaker. Now they want a sauna as well with a 7kw heater. No one thinks the hot tub and the sauna heater can be on at the same time - too much load.
Does anyone know of a switch where the owner could energize the sauna circuit and the hot tub circuit would be de-energized at the same time, all run by a timer. So the owner can flip the switch; power to the sauna; hot tub is de-powered; then after X hours the circuit goes back the way it was before? They could do it manually, but are forgetful and if left off the tub would freeze up.
Not sure the load of the hot tub, guessing it's no more than the sauna.
Any ideas?
Thanks, Jim
 

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I own stock in FotoMat!
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I wouldn't bother with such a Rube Goldberg idea. Upgrade the feeder with one big enough to run the loads.
 
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DA100 MINIFLEX® On/Off Repeat Cycle Timer


Quick Specs...
  • Continuous repeat cycle timing in a compact 1/8 DIN case
  • Fast, easy analog dial setpoint adjustment

A repeat timer like this one wired with two sets of contacts to two seperate contactors would work in this case, but like others have said-it would be just as easy to upgrade the sub-feed. I have used this timer for many controls in Industry & it is very good & reliable. It is made by Eagle Signal & you need to buy a base for it also. Your Contactors would have to be sized for your amp ratings of each load.....................
 

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Head Grunt
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3,270 Posts
As everyone has said just upgrade the service in the sub-panel to handle the load. Otherwise just install 2 sets of contacts with a 3-way switch to control them.
 

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JimmyS
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224 Posts
Discussion Starter · #6 ·
Wow, you guys are fast. I should have mentioned that the feed to this building is buried, in conduit but many bends, over 200 ft. long. They've used up pretty much of the capacity in the house panels too, plus genny transfer panel. It's probably not practical to upgrade the service, though I agree that's the best solution. Maybe they'd go for it...
We really thought we had their needs covered when we built it.
Thanks for all the suggestions. Jim
 

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I own stock in FotoMat!
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Wow, you guys are fast. I should have mentioned that the feed to this building is buried, in conduit but many bends, over 200 ft. long. They've used up pretty much of the capacity in the house panels too, plus genny transfer panel. It's probably not practical to upgrade the service, though I agree that's the best solution. Maybe they'd go for it...
We really thought we had their needs covered when we built it.
Thanks for all the suggestions. Jim
 

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Well, let me weigh in with my stupid but legal and easy solution. :jester:

Get a 3 way switch from Home Depot, the cost .79 cents. The black screw on a 3 way is the common, feed that with a hot wire. Send a wire from one of the brass screws to a small relay that the sauna power passes through. From the other brass screw send a wire to another small relay that the power for the hot tub passes through.

I would charge a customer around $500 to do this. The problem is one relay (or contactor if required) would be on all the time. Make sure the relays are housed in a metal box. The parts cost is less than $100.

Your new 3 way switch acts like an A-B switch, just select the sauna or tub then turn on the desired equipment.

I can come up with a more elegant solution using PLCs but you're looking for something cheap and quick.
 

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Well, let me weigh in with my stupid but legal and easy solution. :jester:

Get a 3 way switch from Home Depot, the cost .79 cents. The black screw on a 3 way is the common, feed that with a hot wire. Send a wire from one of the brass screws to a small relay that the sauna power passes through. From the other brass screw send a wire to another small relay that the power for the hot tub passes through.

I would charge a customer around $500 to do this. The problem is one relay (or contactor if required) would be on all the time. Make sure the relays are housed in a metal box. The parts cost is less than $100.

Your new 3 way switch acts like an A-B switch, just select the sauna or tub then turn on the desired equipment.

I can come up with a more elegant solution using PLCs but you're looking for something cheap and quick.

That doesn't address the timer part of the question.
 

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Well, let me weigh in with my stupid but legal and easy solution. :jester:

Get a 3 way switch from Home Depot, the cost .79 cents. The black screw on a 3 way is the common, feed that with a hot wire. Send a wire from one of the brass screws to a small relay that the sauna power passes through. From the other brass screw send a wire to another small relay that the power for the hot tub passes through.

I would charge a customer around $500 to do this. The problem is one relay (or contactor if required) would be on all the time. Make sure the relays are housed in a metal box. The parts cost is less than $100.

Your new 3 way switch acts like an A-B switch, just select the sauna or tub then turn on the desired equipment.

I can come up with a more elegant solution using PLCs but you're looking for something cheap and quick.
if that were the case, why not just install a transfer switch. But still, no timer.
 

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why not two contactors one normally open and one normally closed feed both with a single circuit and controled by a simple switch type timer. when the timer comes on one opens and the other closes then back to closed and open when the timer goes off.
 

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My amazing feat of electrical engineering does not have a timer. These people are just going to have to learn how to work the switch. If they turn on the tub and it doesn't come on, they will have to flip the switch.

If these people cannot display the cognitive skills God gave chimpanzees, I can rig it to give them a mild shock every time they fail to flip the switch. They'll soon remember the switch...

 

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I don't want to encourage this, but if you want a timer than get a double pole double throw contactor and hook a sp timer switch to the coil.
 

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DA100 MINIFLEX® On/Off Repeat Cycle Timer



Quick Specs...DA200 MINIFLEX® Digital Repeat Cycle Timer




Quick Specs...
  • Repeat cycle timer with digital setpoints and 4 time ranges
  • Compact 1/8 DIN case
  • Continuous repeat cycle timing in a compact 1/8 DIN case
  • Fast, easy analog dial setpoint adjustment
A repeat timer like this one wired with two sets of contacts to two seperate contactors would work in this case, but like others have said-it would be just as easy to upgrade the sub-feed. I have used this timer for many controls in Industry & it is very good & reliable. It is made by Eagle Signal & you need to buy a base for it also. Your Contactors would have to be sized for your amp ratings of each load.....................
I brought this back because it is a practical solution & not very expensive or hard to install. These Timers can run continous with on/off times set by you. That is why they are called repeat. The coil is 120 vac. They have 2 sets of contacts so you can wire them to the coil of each contactor or if you are electrical savvy wired in with the control circuits of your hot tub/ sauna etc...............................
P.S. If you decide to go this route, feel free to email me for any help with the wiring.
 

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I own stock in FotoMat!
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12,985 Posts
Switches, timers, relays, contactors.............

I still think updating the panel would be the best, easiest, simplest and most cost effective solution.

Fix it right, and fix it right the first time.






Otherwise, you end up with

 

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480 Sparky, I think you missed his Post about the Panels, Situation, Etc. It looks like Upgrading panels,in this case, would be a big undertaking in this case.
What I suggested may sound complicated to some , but it really isnt & it is cost effective in this case. I am all for helping out here & not trying to "compete" to who has the best ideas here................
 

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Thom
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4,137 Posts
Let's review.

You built an outbuilding with a steam shower
You added a spa
You're adding a sauna

They can't afford to upgrade the service and sub.

It sounds like they have enough money and are willing to pay for toys, but don't want to waste money on doing things properly and safely.

It's your job to tell them what is safe and responsible, not build some rube-goldberg that will get you in trouble down the road for trying to save them a few bucks.
 

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Tech Geek
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2,654 Posts
Why not set it up so there's an outside light that stays on while they're running the sauna? That way if they forget to turn it off they'll be reminded by the light? Simple and effective.
 

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JimmyS
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224 Posts
Discussion Starter · #20 ·
Thanks again for the responses. Money's not really the big problem, and they are willing to pay for what they play with. They aren't chimps, but we all know people who just can't be relied on to look out for themselves. They are like that.
The double contactor with timer EES suggested is what I'm looking for. We could make it up most likely, I'm just asking to see if there's a ready-made switch that will do that job, with big enough capacity. Of course it should be safe and durable.
I'll investigate the service upgrade, as that seems simplest and best. But I appreciate everyone trying to work this out, too.
Jim
 
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