Controlled Outlets

True, unless you get one with a backup.

Nope. I know a thing or two about this stuff. There are other options, many of them way overpriced, but I haven't seen a particularly reliable one. At a client we decided to roll our own and that was a good decision.

RC has never shown a hint of humor.

gnuarm wrote :

I dunno, I have used internet and ssh -Y to my LAN to access things remotely, and can even look around via the various cams. What is the problem? Just a bit of code. Program some PICs. Even room lights I can control. Check temperature, humidly, radiation, audio, video, inside, outside, can speak to the place, what not. Only requirement is that he cable modem is on. I have some wireless options too, in case internet dies, ham license. You still need power. Have a solar panel, battery backup. Yes maybe I am a freak :-) But it is there so I try it. What protocol, make your own, all sensors units have been designed by me. Much harder to hack.

And how old are they?

A friend of mine had a printer stolen from his place a number of years ago during a B&E, however prior to taking it the burglar pulled the paper out of the tray and tossed it on a table. The police simply pulled the first sheet off the top of the stack and dusted it for prints revealing a nice fat greasy thumb-print.

They picked the burglar up the next day he was a habitual offender already in the system. Most criminals just ain't very bright.

So when he said most fridges are frost free, he was talking about his own little world only.

Rick C.

rol it.

Yes, I believe I said that in the original post. Last summer they were ask ing people to voluntarily cut back on electricity usage at peak times, so I did some experiments on shutting off my AC from 3 to 6 (the hours they ask ed for). I found the temperature in the house only went up by two to four degrees. So I programmed my thermostat to cool the house down a few degree s in the morning and then shut off in the peak period returning to a normal temp afterward. It was not so uncomfortable. By 6 pm it was starting to get a bit warm. I expect this won't be much different shutting it off unti l 7 pm.

A year or so ago I looked into the time of use service after finding a docu ment on the web site describing it. I tried to contact someone by phone an d never got a call back. This year I sent a message through the web site a nd after a couple/few weeks I got a reply that they had changed my service. Ok, but they didn't say when it would go into effect or anything else. S o I sent a reply about it and the guy responded with a veritable tome about the service even comparing my billing this period both on the regular bill ing and the TOU service (he is now using the TOU abbreviation while previou sly I saw TOS used). The TOU service is a dollar higher with no effort to change my usage. The real kicker is the electric car. I will be using som e portion of 100 kWh each week to charge it which can be done off peak.

I'd also like to move other usage off peak which should work ok with the fr idge if I don't open the doors during that time. I can even disable the de frost timer since it will defrost every day! lol

Rick C.

How does an electro-mechanical timer have a power fail backup???

Care to share?

I've not seen much in the way of power fail robust electronics readily avai lable at a low price. Certainly it is not worth rolling your own hardware/ software. If I could find a low price battery backup for an rPi I would co nsider that since you can get an rPi for $10 with built in wifi. Not sure how robust the software would be.

Rick C.

The feature is often called "carryover". Example:

On purely electro-mechanical timers it's the old tick-tock method. Some have a little oscillator and motor but the classical movement and spring is the one I saw most often. When I was young and experienced it for the first time it startled me ... vvvvvrrrrrrt .. POCK. That was when it wound up after install. No need to replace batteries, no leaking batteries, just a few drops of oil every few years.

Not allowed to, it's proprietary to a client of mine.

That's one of tghe (many) issues but you countered that I must be "old and set in my ways". Now you realize it yourself?

It most certainly is worth it. My client now has a system of cast-iron robustness.

Personally I don't trust anything that has foreign code in it unless I know the architects really well. It's up to you. I don't know what the Raspi needs in terms of power but a battery backup can be made with LiIon batteries. If you never let the charge level go above 85% capacity or below 40% they can last almost forever. Even the li'l LiIon flatpack in my Nokia candy bar phone from 2005 (remember those?) still holds up in standby time.

Aside from the defrost timer ours is on the big PG&E timer. When there is a wildfire nearby they said they'll now simply cut power to make things "safe". I guess that's cheaper than fixing the grid, despite sky-high electricity prices.

Anyhow, Rick is looking at things IMO the wrong way. If you really want to make a fridge TOU-capable you have to add some additional smarts inside. You can't do that externally. The controller has to know when the TOU cut-off is approaching and ramp down the temperature accordingly, most definitely in the freezer section if there is one. Then it can sail though several hours of high-rate electricity. Otherwise things will warm up too much and either won't taste good, melt or develop some sort of unhealthy bacteria.

The worst case would be if the fridge/freezer has just completed a defrost cycle and then some external gizmo cuts power because it's 4pm or whatever.

It won't. Read up on how a defroster works in detail. Besides, a well insulated somewhat modern fridge uses very little electricity to begin with. Compared with your A/C and electric car it's totally in the noise.

Then there is the math. I know you don't believe me but it's a fact that a decent controlling device that doesn't lose time during a brief outage or fail within a few years will cost in the serious three-digits. Now how long do you imagine it will take to recoup that cost having moved the fridge consumption out of TOU peak? Will your grandkids still be living?

You sir, are quite the oddball! You are suggesting I need to use a $2100 t imer to control a $500 refrigerator so I can save $10 a month (maybe) on my electric bill!!! Give that a little thought...

Ok, well, thanks for mentioning it anyway... ?

I guess your advanced age is clouding your thinking as well. My comment wa s regarding your suggestion that I use a mechanical timer which is not part icularly reliable unless I get the $2000 version with a mechanical backup.. . Yes, I stand by my earlier statement.

One that is so valuable he must protect anyone else from even learning abou t it much less getting one. Yes, very important... Was your client Profe ssor Farnsworth by any chance?

So you don't drive cars, or watch TV or use a computer???

Rick C.

I think you are a master at over design. The requirement is to save power during peak hours (which change summer vs. rest of year) and not let anythi ng thaw out assuming the user doesn't open the doors. I have been through power outages longer than 4 hours and nothing thawed out. Insulation is a wonderful thing. There is also the thermal mass of the items in the freeze r at 0 degrees F.

How long is the defrost cycle? How much will the temperature rise? How of ten is the defrost cycle? How do you know my fridge has or will have a def rost cycle when I do this?

Rick C.

yeh a modern A+ refrigerator is maybe 150kWh per year

What noise? In many ways the entire utility bill is in the noise. You see m to have made life choices to optimize things that are also in the noise i n the grand scheme of things.

ng?

You are right, I don't believe you because you have not demonstrated that y ou know diddly squat about the controller devices I might use. Rather you have painted a picture of a general distrust not so much different from xen ophobia. I prefer fact based knowledge.

Rick C.

So that's 1 and a half full charges of a Tesla or around 450 miles. Yeah, that seems worth getting on the low cost side of the TOU curve.

I find it funny that while NO ONE has actually talked about using any of the devices I might use for this, lots of criticism has occurred. I guess that's SED!

Rick C.

The problem with fires in California isn't ignition sources. It's building houses in the woods, and putting out fires to increase the fuel load. There will always be ignition sources, and the fires keep getting bigger.

There were big fires here before the Spanish explorers showed up. We're making them bigger.

Two fridges could be switched to the line alternately. Each would cool down when it is powered, but peak power would be cut in half.

gnuarm wrote

What is there to say. I thought about it, and a PIC can run with internal - or xtal oscillator, but still needs setting to correct time every now and then. Either via the internet connection or via for example a GPS module.

Designing the hardware and writing the soft takes at most a day, and building it on veroboard an other few hours.

Cost perhaps 25 $ to 50 $ (with GPS) all together, inclusive big triacs or relays. I would check ali-express and similar, likely the Chinese already have it at a lower price. Box and connectors would be the biggest expense. Should work for as long as FLASH memory holds if designed well. Yes I have something like that here.

You want a hundred? China PCB service. OTOH my fridge does not frost / defrost, once every few month at most I manually defrost the deep freeze part. It is used every day, and the thermostat is a mechanical one. No idea how much power it uses, had it for maybe 10 years. Now calculate how many cents 'trickity you have to save to get the cost of your controller back. IMNSHO you may well be creating a problem that does not exists. If you need help writing the code or designing that thing ask here. The rest is philosophy.

Of course you could design a control module around the ESP8266 that would connect to your WiFi and get accurate time from internet, be programmed using a simple program on your PC or even using a webpage, and cost nearly nothing.

But then, that probably already has been done.