Building a ripple control controller for hot water

[nzoomed]

In NZ we face a power crisis this winter, and they may take action by turning off our hot water cylinders to try and save power. If this happens, i want to be able to make a device that puts a signal in the range of 175 Hz to 1050 Hz, superimposed on the 50 Hz mains , 230v.
How easy would this be to do, as i dont want to be left without hot water!

 

[Mikebits]

Are you saying you want to try and circumvent the turn off signal by adding your own signal to reactivate the valve? Hmm... Sounds illegal.

 

[rjvh]

In NZ we face a power crisis this winter, and they may take action by turning off our hot water cylinders to try and save power. If this happens, i want to be able to make a device that puts a signal in the range of 175 Hz to 1050 Hz, superimposed on the 50 Hz mains , 230v.
How easy would this be to do, as i dont want to be left without hot water!

Hi nzoomed

What are hot water cilinders ??

tanks with water and a heater element

there are other ways to make your water hot

but how would the goverment be able to switch of your hotwater generation in your house without effecting other parts of your system?

Robert-Jan

 

[nzoomed]

not illegal as far as im aware

because most power company customers chose to have it in the past, but in this country, it seems all new homes have it nowdays.

Hi nzoomed

What are hot water cilinders ??

tanks with water and a heater element

there are other ways to make your water hot

but how would the goverment be able to switch of your hotwater generation in your house without effecting other parts of your system?

Robert-Jan

The reason why no other things turn off is because there is a receiver in your meter box, that receives the signals sent down the power lines from the power company which triggers a relay to turn off your hot water cylinder, nothing else is affected through this, we hear ours clicking at least once or twice a day that i can think of, usually in the mornings and evenings

 

[rjvh]

Is it not easyer to over ride the contacts of the relais with a seperate switch

Robert-Jan

 

[nzoomed]

yes it would be

but thats tampering with the meter box, and if the power company found out, well they charge you to get it fixed if they found out

 

[rjvh]

Is the hot water cilinder also sealed by the electricity company so you can't get the wires from the heater element and switch it by your self??

Robert-Jan

 

[nzoomed]

no it is not sealed

if i really wanted to i could wire a direct feed to the cylinder, so that it always got power, if they start cutting off hot water, i could easily do that

 

[Sceadwian]

The first sentence of your post is "Power crisis" and you want to bypass it? The more people like you there are the more brown outs and blackouts there are going to be.

 

[Pommie]

Why not add another layer of insulation to your hot water cylinder. A well insulated cylinder will stay hot for days.

Mike.

 

[RODALCO]

powercrises.

Hi nzoomed, welcome to this forum.

I'm not going into details about this topic but the solutions are already given in the replies.

The NZ powercrisis is a con, we need one so we finally get some proper power stations built. e.g. nuclear or coal fired, north of Auckland.

Our politcians have wasted mega dollars on windfarms which cannot guarantee a reliable supply to the city.

Regards, Raymond

 

[nzoomed]

thanks your right

it is a big con, and ive found other way around it anyway, like thumping the meter i was told will trigger off the relay! lol but i still think it would be real neat project if you could make a controller that sent a signal down the mains! I dont know if it would turn off everyones hot water in your street though. ive seen networking kits called homplug that could send data signals through the mains for connecting your computers together, and that is supposed to only be able to work in your house.

 

[SPDCHK]

it is a big con, and ive found other way around it anyway, like thumping the meter i was told will trigger off the relay! lol but i still think it would be real neat project if you could make a controller that sent a signal down the mains! I dont know if it would turn off everyones hot water in your street though. ive seen networking kits called homplug that could send data signals through the mains for connecting your computers together, and that is supposed to only be able to work in your house.

I have been "Experimenting" with a circuit that works principally on the same way. Superimpose a frequency on the domestic AC lines and with a NE567 PLL detector on the receiving side filter out the correct frequency and use it for control. The problem I have is that it works 100% on static lines (while testing) but the moment I connected it to my AC at home, it tripped the earth leakage and I have an equipment failure rate of about 50% That's BAD!!!! (It either blows the transmitter IC or the receiver IC). And that's where I left it.

The circuit uses the Earth and Neutral wires on the AC circuit for its communication medium. The problem is (I don't know if all earth leakage devices does this, or just mine) the moment I superimpose the frequency (at about 5V) the Earth leakage picks it up and trips out everything.

 

[nzoomed]

we dont have an earth leakage device

in our house, only a circuit breaker or a fuse, which will blow if there is a short to earth, but that only works at close to full mains voltage to earth, ours has tripped over when ive had appliances short to the earth

 

[rjvh]

in our house, only a circuit breaker or a fuse, which will blow if there is a short to earth, but that only works at close to full mains voltage to earth, ours has tripped over when ive had appliances short to the earth

it wouldn't hurt to have one in my opinion but personaly i have on a sertain group a higher trip current (due to conected equipment (welder))

still its safer than having nothing and they're not that expensive anymore

Robert-Jan

 

[mneary]

You use electricity to heat water?

 

[Nigel Goodwin]

You use electricity to heat water?

It's a very common method, usually using an element in an insulated copper tank, the copper tank also normally has the option of being heated from the central heating system, or (in the VERY old days) from a 'back boiler' mounted behind a coal fire.

I used such a system until late 2006, when it was all ripped out and a gas combi-boiler fitted.

 

[mneary]

I had an electric water heater briefly in 1974, ripped it out and replaced with gas as soon as I got my second electric bill.

 

[Nigel Goodwin]

I had an electric water heater briefly in 1974, ripped it out and replaced with gas as soon as I got my second electric bill.

What were you doing with it?, mine was on 24/7 for 25 years, and I never had big bills. I only took it out because the element failed (insulation breakdown, blowing the earth leakage trip). I did buy a new element to try and replace it, but I couldn't get the old element out (I was scared the tank would rip), so we decided to replace the old (pretty crappy) gas central heating totally.

While waiting for the job to be done I borrowed three 1KW isolation transformers from work, wired them in parallel, and fed the immersion from them this stopped the trip blowing, and worked fine.

 

[mneary]

In 1974, US electric rates were about three times as high as gas, per BTU. We were spending about $30 per month (1974 dollars) just to heat the water.

I calculated that the gas unit paid for itself within the first year.