Don't play around with the arduino connected to control your main power , or lights or whatever.
This is Australia where there is rules for everything. It is not safe and not certified by the proper regulation authorities and in an event of a fire or death then you will have to answer for what you have done. The arduino in my honest opinion is just a simple hobby learning tool and to erratic to control important life depending utilities.
Tangles84:
Yea that's my thinking too. I know there is regulations on the wiring. And I'm using relays that are rated and are used on plc systems that are legally used in industrial application. so fault current, over voltage or separation are not the issue. It's as safe as any installation.
exactly what your saying, there is only a 12v signal that can do anything and under any circumstances. (with those signals doing anything in any combination ) there is no safety sitiation. so I cannot see why it cannot be controlled by anything.Edit
The scr and enclosure were din rail mount for the purpose.
Im not sure if the screw down type would be suitable without approvalI've got no problem installing g a board with the relays in it and having it pass all regulations and be safe. I've done this many times with 240v control
if it was turned off or on all outputs stayed on or off or hung or any thing it wouldn't cause any danger.
I can't see why this would be a problem except for regulations as Australia is really full on with their electrical regulations so maybe it needs to be certified.
I'm really frustrated as I called my power authority and they weren't any help. They told me to read x y z rule books. ffs those things are written for lawyers not electricians. so I'm stumped. hence why I'm here lol.
Im in the uk.
A similar problem, I wanted to use scr's to control X 1kw heating elements.
I found a uk approved opto isolated one.
Went looking for a sparkie to do the installation (it had to be certificated).
Conclusion was when put inside a 1.8mm steel enclosure (approved) its fine.
Problem was finding an electrician confident enough to do it.
Part P (domestic) electricians would not touch it.
I eventually found a fully qualified industrial guy who was quite happy once I showed him the equipment, but he was very familiar with scr's and control systems.
Edit
I did use din rail mount scrs though.
Im not sure if the screw down type would be appropriate without approval.
I could understand if you're making a product or doing something more dangerous than normal or messing inside the breaker box but hello, a relay to switch was that 12V?
The 12V switching power supplies I buy are already rated and approved! I don't need no stinking okay to plug one in and use the power... but I'm not in what sounds like child-safe Australia.
I'm 110% confident in not causing a fire or death. I'm an industrial spark who just left a job working on wiring a military aircraft carier ship for Australian navy.
@fransie.
I'm looking at making an embedded system. The arduino is a learning / prototyping tool. if you open up a plc (which we had hundreds on the ship) there is a chip just like the avr chip that is running the system. avr chips are used on numerous life saving equipment. I'm not looking at using on fire systems or oxygen backups or lift motors or co2 monitors. I'm using it to switch on some lights. the avr is actually overkill of what I want to use it for with the appropriate support circuits. it is as safe as any switch that you can install. The avr is not a toy it just needs to be designed well with support circuitry before you let it hold your life on the line.
I'm switching 240 vac .
@Tim yea I've email energy safe asking the hypothetical. I was not very happy with the response last time so I don't have my hopes up. I think the earthed metal enclosure would be a good add on to my finished product though. I believe it has to pass emr testing to pass and high voyage spike test on earth.
The problem is the load side of the controller not the plug in side. the load side will be switching mains. there in lies the problem.
Until very recently, the optocoupler was the only practical choice in providing safety isolation for manufacturers of medical and industrial isolated systems. The arrival of digital isolator has however, changed the situation greatly. Digital isolators offer several advantages over optocouplers. They are more reliable, cheaper and have greater power efficiency compared to the optocouplers.
- optocoupler
- transformer coupler
- capacitor coupler
Most of them have isolated voltage bigger than 3KV.
https://forum.arduino.cc/index.php?topic=327770.msg2264593#msg2264593
Tangles84:
The problem is the load side of the controller not the plug in side. the load side will be switching mains. there in lies the problem.
Yes.
Over here im qualified but not registered with a regulatory body.
So I cannot certify what I do.
My view on this issue is that controlling lights using an Arduino is essentially the same as controlling lights using an electronic time switch.
As far as I'm aware, in Europe a time switch or home automation product would need to be certified that its safety meets "IEC 62368-1:2014 Audio/video, information and communication technology equipment - Part 1: Safety requirements". CSA/UL 62368-1 is a Canadian/America version of this standard. I have had the safety of a product for domestic use certified to a previous national version of that standard. Equipment that is regarded as part of the fixed electrical installation within a dwelling would have to meet some other similar standard.
If you intend to fit your home automation in customers' houses, then I'm sure its safety should be certified; that can be rather expensive! If you are fitting it only in your own home then I would recommend it is removed before you move house.
The basic rule everywhere is not to touch things which are behind your mains wall socket..
What you plug into the wall socket is up to you and you are fully liable for any direct and indirect damages caused by the stuff you are plugging into.
And, the certification for goods and services is usually required when you are going to offer your goods or services commercially. It does not apply usually for your home built stuff used at your home (but you are still liable..).
Hi,
The logic behind our laws,(Australia), is not so much the hardware passing standards, its the workmanship of the associated hardware.
If you can design a safe PCB and assemble it using approved components , doesn't mean you can use a drill and screwdriver and produce the surrounding hardware to protect it and keep the operator safe.
How many people will assemble a metal box and not put earth leads from each separate metal panel to a central point.
As well as not use the proper connecting terminations.
Unfortunately at times there is method in the madness...
Tom...... 
I can only repeat that if you have the qualification you claim, you should also have the experience to know which way to approach your situation.
I am an electrical contractor, have been since the early 80's.
Not prepared to give definitive answers as there is "too much unknown".
Aside from that, chase up the relevant standards and if the particular section is unclear or not covered, then, as I said earlier, a call to the SAA or your contractor association will clarify your position.(both from a legal and practical aspect)
Some may have the opinion that the safety standards in Aus are a bit much, but, I can assure you, if you start playing with systems you do not fully understand and create a dangerous situation, the penalties can be quite severe.
Especially if you have some electrical background and basically should know better.
It could be a long and expensive journey from "idea" to "reality" as far as any certification is concerned so you may want to look at Cbus or similar as an "already approved" system.
bluejets:
I can only repeat that if you have the qualification you claim, you should also have the experience to know which way to approach your situation.
I disagree.
Electricians are trained to know how to install and test electrical power distribution systems, including selection of appropriate equipment and cables. They are not trained to design items of electronic equipment to meet safety and other standards.
I've found channel to go down.
they have a list of regulations that i need to adhere to. also saa aprovals australia I will follow advice and contact them.
so I'll contact them and see what is required for certification. think it will be too much trouble jumping through their hoops. the c ticl doesn't seem to hard but i don't know about saa.
I'll send an email.
I think easier way is just use plc. i would never use cbus. it's the most over rated over priced unit on the market.
can get plc to do the same thing for a fraction of the price.
I'll keep posted my progress ir lack of.
Archibald:
I disagree.Electricians are trained to know how to install and test electrical power distribution systems, including selection of appropriate equipment and cables. They are not trained to design items of electronic equipment to meet safety and other standards.
As my electrician said, the supply and control circuits are safe.
If I chose to plug in my machete wielding robot that's up to me.
I used approved industrial control gear which although costing 100's or 1000's normally , I picked up from the scrapyard for 10.
needed paint but that's just decoration.
Edit.
Don't know about Australia.
Over here I am qualified and have up to date regs.
However registration (to allow me to issue certificates) has an ongoing cost of several hundred per year.
Cheaper for me to pay a registered spark to do the job for me when the occasion arises.
Boardburner2:
If I chose to plug in my machete wielding robot that's up to me.
My understanding is that the Arduino and/or the associated relays are to be part of the fixed wiring of the house, not plugged in, so will probably remain there when the house is eventually sold.
Ah right.
In my case unplugging the control lead would leave the installation safe but inoperable.
Maybe the op can modify his installation so this is possible ?
Archibald:
I disagree.Electricians are trained to know how to install and test electrical power distribution systems, including selection of appropriate equipment and cables. They are not trained to design items of electronic equipment to meet safety and other standards.
That may be, however the op is claiming to be a contractor and under this heading he should know which way to approach the situation.
Boardburner2:
Ah right.In my case unplugging the control lead would leave the installation safe but inoperable.
Maybe the op can modify his installation so this is possible ?
Smart lights are available for home automation that would avoid the need to wire relays into the house lighting power circuits. There are some [here](http://www.maplin.co.uk/c/home-electricals/home-automation#Category:Smart Lighting), including some that work on Wi-Fi.
I'm 110% confident in not causing a fire or death. I'm an industrial spark who just left a job working on wiring a military aircraft carier ship for Australian navy.
@fransie.
I'm looking at making an embedded system. The arduino is a learning / prototyping tool. if you open up a plc (which we had hundreds on the ship) there is a chip just like the avr chip that is running the system. avr chips are used on numerous life saving equipment. I'm not looking at using on fire systems or oxygen backups or lift motors or co2 monitors. I'm using it to switch on some lights. the avr is actually overkill of what I want to use it for with the appropriate support circuits. it is as safe as any switch that you can install. The avr is not a toy it just needs to be designed well with support circuitry before you let it hold your life on the line.I'm switching 240 vac .
You don't need to defend yourself with your job description or how you wont cause a death or a fire.
I am in the trade as-well and found that not everything is black or white. Anyone can over look something and whatever you going to do is still experimental. Yes there is avr and pic micro controllers in all sort off plc devices , but they have been tested and in most cases coded in assembler for better performance. Best of all the corporations can defend themselves with track records and the fact that the plc that they sell will be industry standard that will be certified etc.. I am not trying to burst your bubble, but rather trying to warn you that you could get into trouble. But hey its your life and your decision and "IF" something happens then I hope you thought of a function for that, because mine will be void guilty (){jail}
I don't want to get into trouble. this is why I'm trying to do it legit.
I brought up my job just to show that a fire isn't the problem. I'm competent with high current high voltage applications I want to know about regulations and certification in Australia. I'm not asking to be warned. I'm well aware of the implications.
if this project completely screws up. if it does the worst thing it could. if the program randomly turns all inputs to outputs or randomly switches outputs . if the chip fails. if it hangs, the worst case outcome would be the same as a 4 year old going crazy on all the light switches in the house. I'm not controlling Tesla coils with it. I'm turning lights off and on. Don't think people get jail time for that but I'll look into it.
Ive never worked on PLC written in assembly. all the ones I've worked on use ladder or c.
when you say they (plc manufacturer) have industry standards and certification. this is the specifics I'm asking about. So you haven't burst my bubble but if you have any info regarding testing, regulations, or certification I'm all ears.
can people please not warn me about fires death jail or anything . I'm aware of this. it's exactly why this thread is open.