Hot Tub alarm

I have a hot tub that is controlled by a 50 am relay with a 24 volt coil that is located in basement. I am trying to setup an alarm or push notification to my phone when the GFIC trips. Since the coil is 24 volts the relay stays energized but the GFIC is off. I was thinking of a water alarm like Aeotec use a small 240volt dpst relay connected to the power relay and connect the Aeotec leads to the NO of the small relay and have that send a pushover notification to my phone. Looking for ideas.

So... to test my understanding, you are trying to detect the 24v (DC or AC)?

What about something like a Fibaro Universal Binary Sensor (FGBS-001)? It can handle a power supply from 9-36v DC with 2 inputs (I could not find the max for those inputs though) and has 2 outputs that handle 36v DC or 24v AC. Here is the manual.

No. I am trying to detect the loss of the 220 volt. I need to get a push or alarm that could be heard upstairs when the breaker trips.

Well, if you use a step-down transformer to get to 120 V, you could use a Ring Alarm Extender (v2 if you have a C-7, which can do S2). It is 120 v mains-powered and has battery backup and can send a power fail alert (power change from mains to battery), which you can use in a rule to turn on an alarm or send a notification.

or you could do like i do and just put a temp probe in using the ecowitt weather station that alerts me if temp drops below 100

or there is this 240 switch which i think will still operate when gfc trips not sure:
also may not be enought if your tub is 50 or 60 amp
GE Z-Wave Plus 40-Amp Indoor/Outdoor Metal Box Smart Switch, Direct Wire, 120-277VAC, for Pools, Pumps, Patio Lights, AC Units, Electric Water Heaters, 14285 - -

I may have a solution for you if you have parallel 220v GFIC outlet that you can plugged in phone charger. Most phone that are sold internationally in the past 10 years probably come with 100 to 220Volt charger.

I made my own Zigbee Environment Sensor. It is expandable. At one point, I make power monitoring expansion board.

You just need to plugged in the environment sensor to the phone charger. Then, the power charger to the parallel GIFC outlet. My device comes with battery backup capability. If you plugged in a LIPO battery, when your GFIC outlet tripped, the device will still run for a few hours. At that point when it tripped, It will also tell the hub that the outlet is off. You can do the rest based on your rule.

If you think something like this would work for your need, feel free to PM me.


Just checked my V1, input voltage 100-240V 50/60Hz 30mA.
Sacrifice an extension cord to connect it to the circuit and set up your notifications.
:sparkler: Just make sure nobody can use the extension cord for anything else. :sparkler:

I will vouch for @iharyadiโ€™s sensors as they work great. I have one monitoring my sump pump circuit and I am notified immediately during a power loss or GFI trip.

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Interesting. I just checked the Ring website for specs on my Ring v2 extender devices, and they are only 110-120V, 60 Hz.

However, I pulled one of them out of the wall, and it clearly says 110-240v, 50/60Hz on the sticker on the back, just as you reported.

I also looked on the Ring website for specs on the V1 (which I do not have). The only specs I could find are for the UK v1 version, and that device only supports 110v, 60 Hz.

I'm actually looking for a solution to the same problem, except that the hot tub is at another house. I want to know if the GFI tripped or the tenant messed with some controls and turned it off, etc.

Can't speak for the OP, but it probably isn't to monitor temperature. If the power goes out, the circulator pump isn't running, and if there's a salt water chlorinator and/or ozone generator, it won't work either. In that case, the water isn't being sanitized and if that goes undetected for too long you have a real problem. Unless you're trying to make bio fuel in your hot tub.

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ya i am more worried about the pipes freezing in the winter which is more severe and since it is winter thought the op might be worried about the same thing. and unless you are in the tropics within like 5 hours even in summer the temp will drop below 100 if power is out so not much chance of what you describe before you get an alert.

It was 80 degrees here yesterday :rage: so I tend to forget about things like freezing pipes. If you're in such a climate and the hot tub is outside, that's definitely a concern.

Is the hot tub in range of your HA network? You could mount a vibration sensor on the circulator pump. That would have the additional advantage of letting you know if the pump burnt out, or something went wrong with the control circuit in the hot tub.

Likewise, if you're concerned about temperature you could probably attach a temp sensor to one of the water lines. Or scrape away some insulation and mount it directly to the inside of the shell.

You have two hots on the breaker, (it pulls off each pole in your panel). This feeds a 50 amp relay somewhere in your basement. You don't need to check if each of the two wires that make up your 240 power have tripped, you only need to check one, if one is down you can be sure the other is down as well (it's how your breaker works).

Just wire in a relay on either of the poles (120 volt) and add any zwave/zigbee dry contact sensor to the other side of the relay. If this does end up tripping your GFCI, then use a 220 volt relay and use the same sensor on the other side of the relay.

A zooz zen16 has 3 dry contact sensors built in, if you already have one. Also any flood sensor that allows for hook up of an external probe would also probably work. There are options.

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First option probably would trip the GFCI, as there would be an imbalance in current draw between the two hot legs.

I think the ideal solution would be not monitoring the current at all, but monitoring the thing that you're really interested in (e.g. temperature, pump operation, etc.).

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If you read the OP's post that is not what he is interested in. He wants to know if his hot tub relay in the basement has power. I don't know why everyone is trying to provide an alternative ideas, there is a simple solution to his problem.

GFCI's can be troublesome, but they are designed to check for power leaks to ground (a little more technical than that but I am not going to get into the technical details of gfci), there are devices in a hot tub (control panel, lights, etc...) that do not use 240 volt power like the heater does. When these pull off just one leg of the power the GFCI doesn't trip since there is no leak (imbalance) to ground (what GFCI breakers check for).

Anyway the above solution is straightforward and inexpensive and does exactly what the OP has asked for. If you do actually have a problem with the GFCI, I addressed that in my post, simply use a 240 volt relay.

The OP actually suggests this solution to his problem in his post. I think he is just looking for confirmation that it will work. I am providing him this confirmation as I believe it will work just fine.

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No offense to the OP in any way, but sometimes people don't ask for what they really want, and you have to read between the lines, especially if you're a consultant, solutions implementer, etc.. The OP suggested a possible solution, but didn't state the problem.

I think it's reasonable to assume that the problem is that the hot tub wouldn't be working if the GFCI trips. The relay in and of itself is not the concern. Otherwise why would he have mentioned the hot tub at all?

If you accept that premise, then doesn't it stand to reason that you would ideally monitor the thing(s) that really matter (e.g. temperature, pumps, etc.)? Just monitoring voltage at the relay doesn't mean the hot tub is functioning properly.

Not to get sidetracked here, but a single pole GFCI checks for an imbalance between the current on the hot and neutral conductors. Not all 240v devices require neutrals, so a double pole GFCI must have to detect an imbalance between the two hot lines if there's no current flowing back through the neutral. Depends on whether the OP's hot tub requires a neutral. Some don't.

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Your bang on about the GFCI, but either way if the 120 volt relay doesn't do the trick a 220 volt relay will. You are also correct about sometimes monitoring something else might be easier, but when I read his post I really think he wants to know if the GFCI has tripped resulting in no power, or that there is a service call required. Quick and easy homeowner fix if the GFCI has tripped (although it shouldn't be doing it regularly).

Imagine monitoring the pump and your HE gives you a notification that the pump ain't working, you call a service company and they come out and reset the breaker and give you a bill for $200.00. LOL