Switching 220V on and off « Jee Labs Talk

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Switching 220V on and off

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fireson

There are several posibilities for switching power on and off and I would like to have some feedback on them. The goal is to switch light, electrical equipment and my central heating system on and off. I would not mind if a neighbour would accidentally switch on my light :-) but other things I would like to have a little more secure.
I found an article on Jee Labs http://news.jeelabs.org/2009/04/16/switching-ac/ but since even Jean-Claude is a bit careful with 220V I would not like to use stuff that could eventually set my house on fire. No idea what the insurence would think about home brewed solutions like that. If however they are 'safe' it would enable a lot of fun in the house :-) So do you guys have found solutions for this??
Regards,
Jan

Posted 22/05/2010 11:43:06
jcw

You could consider using opto-isolated triacs, such as the S202T02 (2A) or S216S02 (16A).
I may try something like this one day. When I do, I'll use a plastic box, tie everything down real well so it survives a strong pull on any of the power cables, and perhaps use proximity sensors from behind the plastic for switches so there is not a single metal part which can be touched.
As for safety: use proper separation and proper wire gauge, so that even if this thing fails, it'll blow the 16A fuse in the mains electricity box before catching fire itself, or causing some other nasty accident.
The new Carrier Board w/ Box is probably not a good option, because the two plastic shells can easily separate when dropped. Maybe when wrapped with some zip-locks or something. A case with power connectors is probably better, or perhaps even a re-purposed cheap KAKU switch.
Does it sound like a hassle? I'm afraid it is.
The other way to go is KAKU or FS20 where replay-eavesdropping is not an issue, and perhaps X10-powerline switches with the proper filters for the more critical appliances.

Posted 22/05/2010 17:29:49
tankslappa

I use opto triac drivers to control the 300v trigger for my camera flashes, they work fine. Although these could switch mains power, they can't handle the current, that's why they are triac drivers, you hook a big triac onto the output. I use MOC3020, but you're probably best off getting a zero crossing triac to reduce clicks and pops with loads connecting and disconecting mid-cycle.
There's a nice circuit here (but he's not using zero crossing triacs either) http://hmmtheresanidea.blogspot.com/2008/09/triac-mains-switching.html
As for safety, read the spec of the big triac and stick to it. If it says heat sink , then use one (careful as many triacs do not have isolated heat sink tabs, they connect to one of the legs). Fuse them suitably.

Posted 22/05/2010 18:14:49
fireson

Thanks guys for the info!
I think I will use the FS20 for switching the lights and maybe build something myself for the 'important' stuff :-) Just to make sure, are the JeeNode and JeeLink capable of using FS20 without any modification? Just a bit puzzled because of the OOK articles, is OOK used for scanning 'anything' in the 868 frequency?
Would the JeeNode be able to control/read the Plugwise circles? They use the ZigBee protocol which is opensource. That would enable me to not only turn power on and off but also measure the power consumption. And they have a standby killer on board...

Posted 24/05/2010 09:56:49
jcw

Yes, the RF12 driver can send OOK signals at 868 MHz. It can't receive 'em, and it won't be as strong a signal on other OOK bands. But for 868 send, it works quite well.
No, JN can't control/read Plugwise. Ask mdamen about details, I think he's the expert on that :)

Posted 24/05/2010 10:18:42
fireson

Is it a software or a hardware limitation that the JN cannot receive FS20 signals? Do you maybe have some links on articles about differences in these protocols, just to prevent me from asking 'silly' questions :-) It would be nice to control everything from one system!
I read the website of mdamen, very interesting! But before asking him, would this also be a hardware or software limitation?

Posted 24/05/2010 11:22:26
jcw

Hardware limitation. See ook-receiver/> for more info.

Posted 24/05/2010 11:55:02
amvv

I use a FS20 switch to switch my central heating boiler on and off, not the regular switch on the plug, but one that can switch loads on a different circuit (I can check the reference if you wish to know the exact reference). You could use one of those controlled from a JeeNode.

Posted 24/05/2010 18:44:11
fireson

@amvv; if it's not too much trouble I would like to see what you are using!
@jcw; I studied it in more detail, I must admit it's a little overwhelming in the beginning :-) What I am looking for is some sort of OOK plug you made which can interface the JeeNodes to the FS20/Kaku world. For example if someone turns the light on manually and my roomboard doesn't detect motion after 1 minute the light should be turned off. In this scenario I need to monitor the status of the FS20 switch. Would the OOK plug with the ELV receiver, and possibly transmitter as well, be a good gateway solution? If I have one gateway the other nodes could use it as well since the range of the ELV components should be sufficient. Or do you have a better suggestion?

Posted 25/05/2010 10:26:19
jcw

For 868 MHz transmission, you don't really need extra hardware IMO. Yes, the ELV receiver sounds like an excellent option for receiving. Keep in mind that the standard FS20 switches have an on/off button on them, but that pressing it won't transmit anything (normal FS20's can only receive). That means it's impossible to be 100% certain of the actual on/off state of the switch.
Maybe we need some power-switching option based on JeeStuff after all. Hm, those darn high voltage / safety aspects :(

Posted 25/05/2010 12:11:43
sysrun

Possible solution: Solid state relays ?
BOIElectricalComponentsSuppliesET&hash=item19bc8b1f2d>

Posted 25/05/2010 12:30:33
jcw

Yes, looks like an excellent option. I need to look into resistive vs. inductive load issues.
(I added <>'s around your link to make it "live" - that's the Markdown syntax)

Posted 25/05/2010 15:20:24
amvv

@FireSon: The switch I use is a FS20 AS1
http://www.elv.de/output/controller.aspx?cid=74&detail=10&detail2=11174&flv=1&bereich=&marke=
Controlled by an FHZ1000 via a computer, but you could control it using a JeeNode.
Indeed, all these ELV switches only receive. If you use the button on them, they do not inform anyone about the change of state. So, to be sure to turn something off, you must send the command even if you don't know whether it is on or not.

Posted 25/05/2010 21:29:15
fireson

Thanks amvv for the info!
Searching the internet I found product/32979/977753>
1 channel toggle relais for 4,90 euro
mode toggle = drukken is aan, nog een keer drukken is uit. 1 kanaals ontvanger Code Type: Fixed Code Output Mode: Momentary Supply Power: 12VDC Quiescent Current: 8mA Operation Current: 25mA less Relay: 3A 220VAC, 3A 30VDC Dimension: 38mm×28mm×15mm
Also a 1 channel transmitter for 3,00 euro
product/32979/966783>
Also lots of other relayboards available, all from What do you guys think? Could they be controlled from a JeeNode?

Posted 25/05/2010 22:15:15
digit

I've had a latching relay connected to a JeeNode once; basic thought was to keep power usage to a minimum; all you need is a short pulse to change the relay state and this state will not be influenced by a power failure. Another thing to consider is that when you start switching things, you'll definitely want ACK; i can live with missing a sensor reading sometimes, but not with this.

Posted 25/05/2010 23:29:22
tankslappa

Some interesting stuff there. How about a little sideways thought...
Have you had a look at any of the X10 stuff? It's been around for ages, but its original function was home automation. It mainly works with data overlaid on the mains wiring, which is good from a security point of view, but will require a little ingenuity with the JeeNode... From a quick check of what is available, there seem to be wireless to X10 interfaces for under UK £30 which received messages from a handheld remote over 434Mhz and then send them over the mains to command remote devices... And we all know a little board that can talk on 434Mhz don't we ;-)
Going the X10 route would mean you could use off the shelf remote controlled sockets without the worry of having to build "High voltage" devices.

Posted 26/05/2010 02:11:32
digit

For X10/A10 look here:

Posted 26/05/2010 06:51:39
patrick

With relays in critical control setups you would like some sort of feedback if what you want to control is actually working. I had a triple phase (380V) relay for my electric heating system broken. One or two of the phases were always on. This overheated the relatively simple system. Water > 100 degrees, steam, overpressure etc etc. not to mention the electricity bill. System failure detection in these cases is advisable. If you switch off, it HAS to be off. The temperature can be an indicator. Taking action on it is harder. (2nd relay to switch off for sure ?)

Posted 27/05/2010 10:15:55