How would one proceed controlling a 220v 2A source? Relay would seem natural but 5v wont really do much for most relays and I only have relays for 9v and 12v laying around that can do 220v. So does anyone have an idea how to either drive the 9v/12v relay or another way of turning 220v on and off with a digital port on the arduino?
I know it says motors but try this:-
http://www.thebox.myzen.co.uk/Workshop/Motors_1.html
However, for direct 5V control I would use a solid state relay.
So does anyone have an idea how to either drive the 9v/12v relay
You could probably get a reed relay with an operating current of 10 or 20mA so direct-drive capable, and use the contacts of that to drive a higher-powered relay.
But an SSR is preferable.
Use a solid state relay, for 220VAC you have a manufactured circuit that will be safe to implement.
Optek OSSRD1001A -- OSSRD1006A are though hole mount SIP units for 250VAC from 3A to 40A Max Current
Inputs for the above are 5-12Vdc with a minimum output current on all at 0.05 A
Optek OSSRD0001A -- OSSRD0004A are panel mount units with screw terminals capable of handling 250VAC from 10A to 40A Max Current
Inputs for the above are 4-32Vdc with a minimum output current on all at 0.05 A
http://www.optekinc.com/viewparts.aspx?categoryID=70
To drive the current relays you have, you could use a Darlington opto-isolator. Make sure you have a reversed diode across the relay to suppess the collapse current.
Here's the standard circuit using a common TIP-102/120 for higher current coils -> Arduino Playground - HomePage
That is realy easy, use any relay you want, 12V 9V 5V or what ever.
Using any NPN transistor, EJ: 2n2222, bc548 any.
RELAY- VCC (12,9,5 etc)
RELAY-COLECTOR
Arduino I/O ----2K2----BASE :o
GND---EMITER
Best Regards
Frank
That is realy easy, use any relay you want, 12V 9V
It isn't at all easy if you don't have a 12V or 9V supply.
It isn't at all easy if you don't have a 12V or 9V supply.
Right, and dealing with the EM pulse from the collapsing field when you turn the coil off isn't fun even if you do have a supply. It's doable, but an SSR is easier.
I used a SSR when I built a project that controls 220V from the arduino. The SSRs I used (got 'em cheap off ebay) wanted more current than an arduino pin could provide so I used the 2N2222 circuit to drive it (could have driven each side of the SSR with a separate pin, but I already had the board fabricated and the 2n2222 was an easier retrofit).
You can find SSRs than can be driven directly from an arduino output. That is by far the simplest way to do it.
-j