Room control

So I cannot use a 5V relay to switch fan and lights on and off? I thought I would use 2 5V relays for one switch, one to get the current state of the main switch and the other to control the current flow.

What I want to achieve : If the main switch is on and a command is given to switch it on the 2nd relay is switched on.
If main switch is switched on the start the 2nd relay.
I want the main switch and arduino to be in series with the main switch being well main.

niner wrote:
What I want to achieve ....

Unfortunately, I am confused with the total lack of your clarity in describing what you want to achieve.

niner also wrote:
I can't connect it with ethernet as it would look ugly and wife shield is not economical (?)

You can't connect or you prefer not to connect?
Yes, a 'wife shield' is not so economical, but a wife, well, she is very useful and beautiful too, especially compared to the 'ugly' ethernet!
I am guessing English is not your preferred language?

If you are going to be playing around with AC as you mentioned, and if that is mains voltage AC, then you better get very clear about what you are wanting to achieve and how you will do this. Understand the risks involved with mains voltage or do not even attempt this if you have no skills or understanding.

Paul

Everything that rockwallaby said as well as: There are devices out there that you can control the mains with that are relatively safe, but for us to suggest them, you need to be a little more clear on what you want to do. The ceiling fan, can you point us to an example? What is your mains voltage? If you're using CFL lights or not. Do you only want to control the lights and fan? What kind of fan controller do you have. etc.

For example this device can be used to control mains connected devices with an Arduino: Powerswitch tail 2 : ID 268 : $25.95 : Adafruit Industries, Unique & fun DIY electronics and kits
And there are ways to adapt various remote devices to being controlled by an arduino. So, is your fan remote controlled?

These are the kinds of things that you need to think about and describe to us so we can make reasonable suggestions.

rockwallaby:

niner wrote:
What I want to achieve ....

Unfortunately, I am confused with the total lack of your clarity in describing what you want to achieve.

niner also wrote:
I can't connect it with ethernet as it would look ugly and wife shield is not economical (?)

You can't connect or you prefer not to connect?
Yes, a 'wife shield' is not so economical, but a wife, well, she is very useful and beautiful too, especially compared to the 'ugly' ethernet!
I am guessing English is not your preferred language?

If you are going to be playing around with AC as you mentioned, and if that is mains voltage AC, then you better get very clear about what you are wanting to achieve and how you will do this. Understand the risks involved with mains voltage or do not even attempt this if you have no skills or understanding.

Paul

I meant wifi, friggin' auto correct.
Sorry for not being clear enough.
Question 1 : I want the arduino to do the task of switching the lights and fans on and off (like a normal switch) according to the input it receives from the bluetooth module. Can I do this with the help of a simple 5V relay?
Question 2 : How can I use AC to give the arduino high/low input? When main switch is on high, when off low? Like the sensors we use with DC?
Thanks

draythomp:
Everything that rockwallaby said as well as: There are devices out there that you can control the mains with that are relatively safe, but for us to suggest them, you need to be a little more clear on what you want to do. The ceiling fan, can you point us to an example? What is your mains voltage? If you're using CFL lights or not. Do you only want to control the lights and fan? What kind of fan controller do you have. etc.

For example this device can be used to control mains connected devices with an Arduino: Powerswitch tail 2 : ID 268 : $25.95 : Adafruit Industries, Unique & fun DIY electronics and kits
And there are ways to adapt various remote devices to being controlled by an arduino. So, is your fan remote controlled?

These are the kinds of things that you need to think about and describe to us so we can make reasonable suggestions.

I will just use the arduino to switch things on and off.
One switch, one fan, one CFL, one tubelight, all this from the already present switch board.

OK, a relay can switch AC (mains) current as well as DC. You will need to consider the current and voltage ratings of the relay contacts you want to use as well as the current draw of the relay coil. Some of those little relay boards for the arduino pull a lot of power when you have two or three of them activated and it can suck down your power supply. Most of the relays will run the lights and the fan. Ceiling fans use less than 100 watts and CFL lights or fluorescent tubes are less than that also, so a relay that has contacts that can handle a couple of amps will do fine.

The problem that is difficult to overcome is having your wall switch work as well as the arduino. For example, you can turn the lights on from the switch, then turn them off from the remote control. But then, when you want to turn them on from the switch again, it won't work. This takes special wiring considerations. This kind of thing is exactly like the lights in a hallway with a switch at each end; there are things you have to do special to make it work.

Ceiling fans are the same basic way. If your control of the fan means you want to vary the speed as well, there are special things you have to do. If you have a remote control for the fan, you can leverage the remote such that the arduino can do things with it.

niner wrote:
Question 2 : How can I use AC to give the arduino high/low input? When main switch is on high, when off low? Like the sensors we use with DC?
Thanks

DON'T DO THAT

Please understand the difference between using and Arduino to control a 5V relay used as a switch for the mains AC (the two circuits are isolated, you may figure the Arduino pressing a button) and feeding 220V AC into the Arduino. You don't need to apologize for your English but you need to understand what we are telling you.

rockwallaby wrote:
If you are going to be playing around with AC as you mentioned, and if that is mains voltage AC, then you better get very clear about what you are wanting to achieve and how you will do this. Understand the risks involved with mains voltage or do not even attempt this if you have no skills or understanding.

Question 2 : How can I use AC to give the arduino high/low input? When main switch is on high, when off low? Like the sensors we use with DC?

As previously pointed out, you can't just connect it. However, I don't think that's what you meant. You probably want to know how to sample to see if mains voltage is available somewhere (like after a switch). Here's a pretty good way to do it, and it can be done pretty safely this way:

http://www.simple-electronics.com/2012/02/isolated-ac-power-line-interface.html

draythomp:
OK, a relay can switch AC (mains) current as well as DC. You will need to consider the current and voltage ratings of the relay contacts you want to use as well as the current draw of the relay coil. Some of those little relay boards for the arduino pull a lot of power when you have two or three of them activated and it can suck down your power supply. Most of the relays will run the lights and the fan. Ceiling fans use less than 100 watts and CFL lights or fluorescent tubes are less than that also, so a relay that has contacts that can handle a couple of amps will do fine.

So, this http://dx.com/p/arduino-4-channel-5v-relay-module-expansion-board-137109 won't work?

draythomp:
The problem that is difficult to overcome is having your wall switch work as well as the arduino. For example, you can turn the lights on from the switch, then turn them off from the remote control. But then, when you want to turn them on from the switch again, it won't work. This takes special wiring considerations. This kind of thing is exactly like the lights in a hallway with a switch at each end; there are things you have to do special to make it work.

That is exactly why I want to see if the switch is on or not. I can override it by turning the switch off and then on, this would tell the arduino to switch the relay on.

draythomp:
Ceiling fans are the same basic way. If your control of the fan means you want to vary the speed as well, there are special things you have to do. If you have a remote control for the fan, you can leverage the remote such that the arduino can do things with it.

I don't have a remote control for the fan. It is an old electric regulator, but I am not sure so I'll leave that for the moment.

spatula:

niner wrote:
Question 2 : How can I use AC to give the arduino high/low input? When main switch is on high, when off low? Like the sensors we use with DC?
Thanks

DON'T DO THAT

Please understand the difference between using and Arduino to control a 5V relay used as a switch for the mains AC (the two circuits are isolated, you may figure the Arduino pressing a button) and feeding 220V AC into the Arduino. You don't need to apologize for your English but you need to understand what we are telling you.

rockwallaby wrote:
If you are going to be playing around with AC as you mentioned, and if that is mains voltage AC, then you better get very clear about what you are wanting to achieve and how you will do this. Understand the risks involved with mains voltage or do not even attempt this if you have no skills or understanding.

I was not apologizing for my English I was apologizing for not being clear.

draythomp:

Question 2 : How can I use AC to give the arduino high/low input? When main switch is on high, when off low? Like the sensors we use with DC?

As previously pointed out, you can't just connect it. However, I don't think that's what you meant. You probably want to know how to sample to see if mains voltage is available somewhere (like after a switch). Here's a pretty good way to do it, and it can be done pretty safely this way:

simple-electronics.com

Yes! This is exactly what I meant. Is there another way to achieve this? Maybe with relays?

Another way is socket/plug with IR remote control.You can decode IR signals from remote control and send it from arduino with an IR led.More easy and safe way no relays,no cables....AC 220 Volt is danger!!!If you think is difficult decode IR signals connect directly remote control with arduino.First the safe and your life and after your project.Inside arduino sketch you can put extra code for TV,Hi-fi,A/C and with bluetooth shield you can make all in one remote control for all your devices from android smartphone!No wires,no cables.

User ----> Android+Bluetooth------->Bluetooth shield+Arduino+IR led----->Send IR signals devices ( small local home automation )

antkan:
Another way is socket/plug with IR remote control.You can decode IR signals from remote control and send it from arduino with an IR led.More easy and safe way no relays,no cables....AC 220 Volt is danger!!!If you think is difficult decode IR signals connect directly remote control with arduino.First the safe and your life and after your project.Inside arduino sketch you can put extra code for TV,Hi-fi,A/C and with bluetooth shield you can make all in one remote control all your devices from android smartphone!No wires,no cables.

Something like this?

Well it is better, and easy but I won't be able to use the switch that are there already.

Yes friend.Is very nice project if you try to decode IR signals.If you want i help you step by step...Look there....http://learn.adafruit.com/ir-sensor/overview....also i had decode my A/C toyotomi and i have create a library for this....SUPER IR ANDROID APPLICATIONS - ARDUINO PROJECTS

If you use remote sockets you must on the device first from switch device permantly and control from remote socket....

antkan:
If you use remote sockets you must on the device first from switch device permantly and control from remote socket....

That is what I don't want, I want the switch to function independently too.

You can connect ... double cables one for remote control and one for manual switch....two switches parallels...

antkan:
You can connect inside device double cables one for remote control and one for manual switch....two switch parallels...

But then if I turn the switch off and the remote switch is on the lights will not turn off.

Ok....switch off and from your system for off...device.Work as OR gate... :wink:

antkan:
Ok....switch off and from you system for off....device.Work as OR gate... :wink:

What if I loose the remote? :stuck_out_tongue:
I just want them to work independently, draythomp pointed me to this. Any better(easy) way to do this?

Why loose? Work as OR gate you do not loose the remote function....

antkan:
Why loose? Work as OR gate you do not loose the remote function....

OR gate?