switching the immersion heater on remotely using GSM

How about so,etching like the Nest system?

I an turn on my heating and ventilation from a mobile anywhere in the world. Admittedly it had a normal thermostat when we moved in so I guess the control system was there already and it just switched the current system on but might be worth a look


W.
 
simonfraser said:
this would do the job no prob:

https://www.amazon.co.uk/dp/B01CKXSJRU?ref_=pe_780071_41837251_dpLink
except the switching capacity is 3A 220V
and i have a 2kW 220V element

so could wire this in
12v Dc 8 Pin Relay 2 Pole
then it needs a box to put the extra bits in

sledge hammer and nut comes to mind

is there a simpler solution ?
Click to expand...

Yes, switch it on when you get to the boat ;)

Or, fit a DIN rail relay in the consumer unit: Non-Latching Relays | RS Components

I use one of these to automatically control my mains charger from the battery monitor: https://cpc.farnell.com/finder/22-2...lar-1no-1nc-12vdc/dp/SW03919?st=finder relays
 
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PaulRainbow said:
The questions was

Not "will it do the job".
Click to expand...


Well tell us "is there a simpler solution"

Using a DIN rail mounted relay for a single relay is overkill when you just screw a octal relay base next to the GSM receiver.

Of cause a 2 pole relay will allow both line and neutral to be switched althrough a single pole would do the job but may need some proper earthing of the neutral and possibly a RCD.

I suppose you would criticise me what ever I posted.
 
Rogershaw said:
Well tell us "is there a simpler solution"
Click to expand...

I already did.

Using a DIN rail mounted relay for a single relay is overkill when you just screw a octal relay base next to the GSM receiver.

Of cause a 2 pole relay will allow both line and neutral to be switched althrough a single pole would do the job but may need some proper earthing of the neutral and possibly a RCD.
Click to expand...

There is not only no need for "proper earthing of the neutral", it would be wrong to do so, there should only be a single PE-N connection, making another one will just trip the RCD. There is also no need for an additional RCD.

It's a very simple case of fitting the relay in the consumer unit, connect the NO terminals of the relay to the neutral and live of the MCB, along with the neutral and live connections for the immersion element.

A 12v negative connection is made to the relay switching coil negative terminal.
A 12v positive cable is connected to the switching coil + terminal and the immersion switch OUT terminal.
A second cable is connected to the switch OUT terminal and the relay OUT terminal.
12v positive cables are connected to the relay IN and switch OUT.

The GSM relay will energise the relay coil, as will the existing switch. Wiring is minimal, just a pair of 12v DC cables. Everything is enclosed. Switching is still double pole.

12v wiring should obviously be suitably fused and the switch should be marked as being 12v to avoid possible confusion in the future.
 
simonfraser said:
'Using a DIN rail mounted relay for a single relay is overkill when you just screw a octal relay base next to the GSM receiver'

i can just surface mount that in a locker ?
does not have to go in a box ?

(all this relay is going to do is make or break the power)
Click to expand...

You can surface mount the base, but it will need to be in a location where the relay cannot be damaged or got wet, or the connections could be touched or shorted. Remember, you're switching 240v AC. Normal practice would be to fit such a relay in an electrical cupboard or a suitable enclosure.

You would need to connect the relay to a 240v live and neutral, to the immersion element live and neutral and to the GSM relay. 12v supplies need to be fused and the 240v supply must be connected after the RCD and MCB.
 
PaulRainbow said:
You would need to connect the relay to a 240v live and neutral, to the immersion element live and neutral and to the GSM relay. 12v supplies need to be fused and the 240v supply must be connected after the RCD and MCB.
Click to expand...

The OP already has a 2kW 220V element which is powered some way and the OP is hot asking how to install the 2kW 220V element just a GSM control so the relay would simply be connected inline with the 2kW 220V element . For easy of wiring it would be good to mount close to the 2kW 220V element. The power for the relay and the GSM unit would come from the boats 12Volt system anyway.

So what's easier than that.

Simon
Mount the relay as close to your 2kW 220V element, disconnect the wires that go to the element to the 2 different common relay contacts and then connect from the NO contacts to the element. Then wire the relay coil + to the NO connect on the GSM receiver and the negative to the negative power input on the GSM receiver and the common on the GSM receiver to the + power input of the GSM receiver.

The only thing to do is connect 12VDC positive and negative from a your main distribution after an existing fuse/circuit breaker to the GSM power input.


There is a rain proof version of the same unit if you wish.

Rain proof version RTU5024 GSM Gate Door Opener GSM Relay Remote Switch 717209382669 | eBay
 
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Rogershaw said:
The OP already has a 2kW 220V element which is powered some way and the OP is hot asking how to install the 2kW 220V element just a GSM control so the relay would simply be connected inline with the 2kW 220V element . For easy of wiring it would be good to mount close to the 2kW 220V element. The power for the relay and the GSM unit would come from the boats 12Volt system anyway.

So what's easier than that.

Simon
Mount the relay as close to your 2kW 220V element, disconnect the wires that go to the element to the 2 different common relay contacts and then connect from the NO contacts to the element. Then wire the relay coil + to the NO connect on the GSM receiver and the negative to the negative power input on the GSM receiver and the common on the GSM receiver to the + power input of the GSM receiver.

The only thing to do is connect 12VDC positive and negative from a your main distribution after an existing fuse/circuit breaker to the GSM power input.


There is a rain proof version of the same unit if you wish.

Rain proof version RTU5024 GSM Gate Door Opener GSM Relay Remote Switch 717209382669 | eBay
Click to expand...

There is no need to fit the relay close to the element, that's just nonsense.

The way you describe above, the immersion heater cannot be manually turned on. You would have to leave the manual switch on all of the time, then use the GSM controller to turn it on/off. If the manual switch is off, it cannot be turned on remotely by GSM.
 
PaulRainbow said:
There is no need to fit the relay close to the element, that's just nonsense.

The way you describe above, the immersion heater cannot be manually turned on. You would have to leave the manual switch on all of the time, then use the GSM controller to turn it on/off. If the manual switch is off, it cannot be turned on remotely by GSM.
Click to expand...

You just cannot help yourself always nitpicking my posts.

We don't have a circuit of Simons boat so its difficult to give pedantic info.

We don't know how Simon operates currently the element, he my like ne use the MCB and don't wish to have an alternate way of switching on his element. I use the circuit breaker to switch on my water heater.

You criticized me for not answering his "is there a simpler way" Now you are possibly adding an extra switch

Simon did not give any further details and I consider Simon to have enough knowledge to work it out. If he does not I an sure he will ask.

Of cause you don't need to mount the relay next to the element but it can make the wiring shorter depends on the mechanical arrangement, which we don't have any idea of.
 
Rogershaw said:
You just cannot help yourself always nitpicking my posts.
Click to expand...

Well, if you insist on posting stuff like this...........

We don't have a circuit of Simons boat so its difficult to give pedantic info.
Click to expand...

Oh, so you do have one, which makes your suggestion correct ?

We don't know how Simon operates currently the element, he my like ne use the MCB and don't wish to have an alternate way of switching on his element. I use the circuit breaker to switch on my water heater.
Click to expand...

Doesn't matter that you use the circuit breaker to switch yours on, if Simon follows your advice he still won't be able to manually switch his on and you wouldn't be able to manually switch yours on, as you have interrupted the mains supply at the element. If the GSM unit fails, no hot water. If the relay fails, no hot water. If out of cellular range, no hot water.

Who wires a boat hot water system up so that it is dependant on a cellular signal ?

Of cause you don't need to mount the relay next to the element but it can make the wiring shorter depends on the mechanical arrangement, which we don't have any idea of.
Click to expand...

The heater element will get its 240c supply from the consumer unit, no matter what the boat is. It's a simple matter of remotely switching that supply. Easily done from the supply end with the addition of a pair of 12v wires. Correctly wired, double pole isolation is maintained and the heater can still be manually switched on/off when onboard without a requirement that a cellular signal is available.
 
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I’ve recently needed to do something somewhat similar, to avoid the water heater running all the time the boat‘s on shore power. We don’t have a switch for the heater, which wasn’t previously a problem as we didn’t have power at our home berth so would only be plugged in when visiting a marina and would want hot water anyway. This winter was the first time we had power when the boat wasn’t in use.

Obviously we could just turn off the MCB for the heater, but it’s in a consumer unit behind a panel and very easy to forget when leaving the boat. So I decided to add a relay switched by the 12v system - turn off the main battery switch and the water heater goes off with it, even if the 240v side is still live to run the battery charger and perhaps a dehumidifier in the winter.

Given the choice, I would definitely have used a DIN rail relay because it made the 240v wiring easy and kept it all in one place (the consumer unit). No meddling with the existing neatly-installed wiring to the heater, just moving some things around inside the box. Unfortunately there turned out to be no spare ways in the consumer unit, so I did end up making up a little circuit board in a separate enclosure - but DIN rail definitely would have been a lot quicker and easier if I’d had the space.

On my board I used one of these Schrack relays as used in cookers, fan heaters, etc: TE CONNECTIVITY RFH34012WG RELAY, PCB, POW, VERT, N/O, 16A, 12V | eBay . The 240v terminals can take spade connectors which seemed a good secure way of making the connection.

Pete
 
simonfraser said:
so true :)

'Simon did not give any further details and I consider Simon to have enough knowledge to work it out. If he does not I an sure he will ask.'

PR nitpicking - never :ROFLMAO:
Click to expand...

Roger thinks that anyone who disagrees with him is nitpicking and/or being aggressive, especially if it's me. :)
 
PaulRainbow said:
Roger thinks that anyone who disagrees with him is nitpicking and/or being aggressive, especially if it's me. :)
Click to expand...

You could not be further from the truth, but you do seem to be aggressive with me and I don't know why but I do have my suspicions.

After all I posted a reply to Simon first and you came back criticizing my post
As you did not post an easy solution how could I disagree with your solution as you did not give one.

If you disagree with what I say why do you keep post. In my view its up to the OP to decide how he wishes to go forward and its his right, not yours or mine.

If Simon wises to do it your way so be it it's his decision and that what important.
 
Rogershaw said:
If you disagree with what I say why do you keep post. In my view its up to the OP to decide how he wishes to go forward and its his right, not yours or mine.

If Simon wises to do it your way so be it it's his decision and that what important.
Click to expand...

That's very true, but the OP needs to be aware of all of the facts, to enable him to make that decision.

I posted a simple, safe and sensible solution. There are other simple safe and sensible solutions. But you stated that the DIN rail relay was overkill, which is, of course ridiculous. You went on to talk about earthing the neutral if a single pole relay was used and adding an RCD. Both of those are unnecessary and an addition PE-N connection would cause the RCD to trip, rendering the entire shore power installation unusable.

You then gave a more detailed account of how it should be wired, claiming that the relay should be mounted near the heater element, which is wrong again. Your wiring instructions also mean that there would be no way to manually operate the water heater and it would be unusable without a cellular signal.

The reason i have to keep replying is to correct your mistakes, so the OP can make a safe and informed decision.
 
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