Switch ac

Hello all I want to switch ac voltage 220 10A , any good element except SSR and relay.? Thanks

any good element except SSR and relay.?

What's the problem with a relay or solid state relay?

If you build something solid state yourself, you are in-effect building your own solid state relay. I've done that using a TRIAC and a TRIAC-driver opto-isolator (and a couple of resistors).

Solid states are too big for my PCB and normal relay has sound. I just want to switch as on and off. Any better element. Thx

I made my own solid state relays for the same reason.

[u]MOC3010[/u] series or MOC3031 series opto-isolators can drive a TRIAC rated at 230V/10A or more, and you've made your own solid state relay. The datasheet shows you how to connect a TRIAC.

You'll probably need a heatsink on the TRIAC. I used TRIACs with insulated mounting tabs, and I mounted them inside an electrical outlet box as a heatsink (the kind of electrical box that's normally mounted in the wall).

And, you might want to buy some extra parts... Whenever you're working with high voltages & currents, the odds of frying something go up... I haven't fried anything, but the 1st time I did this several years ago, I tested & debugged it with a 12VAC transformer and a 12V incandescent lamp.

DVDdoug: You'll probably need a heatsink on the TRIAC.

By which time it will likely be the size of a SSR of course. :grinning:

DVDdoug: I used TRIACs with insulated mounting tabs, and I mounted them inside an electrical outlet box as a heatsink (the kind of electrical box that's normally mounted in the wall).

And you grounded the box very carefully.

And you grounded the box very carefully.

Good point! I should have said isolated tab. I didn't have to use a mica insulator kit. So it would take a failure of that isolation, or a broken internal wire touching the box (or a wiring error) AND ground failure for it to become unsafe.

...I'd say most of the danger comes during testing/debugging with you've got the cover off and you're probing around, and/or there might be a wiring error.

...Plus, I'm in the U.S. with "only" 120V. :D :D :D

Yes,I think I should give MOC3010, pulse to control AC signal, I want to switch it like relay. What can I do? Thanks

What can I do?

Drop your unrealistic preconditions.

If you don't want to use: 1-SSR 2-RELAY 3-TRIAC

guess what ? You're SOL... (for you non-americans, that's "SXXT Out of Luck"

DVDdoug: Good point! I should have said isolated tab.

I assumed that and wasn't worried about which you used.

Just as long as your box is grounded. :astonished:

Is there any reason that paralleled NPN and PNP transistors can't be used to switch AC?

leoncorleone: Hello all I want to switch ac voltage 220 10A , any good element except SSR and relay.? Thanks

Well, you asked the question.

A mechanical switch will do the trick just fine.

Did you want to ask something differently?

Is this for one or two devices, or a large production run?

smeezekitty: Is there any reason that paralleled NPN and PNP transistors can't be used to switch AC?

Lots of reasons. Mainly getting transistors to operate at those voltages.

What is your thinking? Using two transistors is going to take up more space than one triac!

Hi, What is the application and how small a PCB?

Tom... :)

If you said this:

Is there any reason that paralleled NPN and PNP transistors can't be used to switch AC?

The normal response from ANYONE would be this:

What are your qualifications for electronics ? (or rather I should say "The fact that you asked that question suggests that you have none".)

Why ?

Well, let's look at what you said:

Is there any reason that paralleled NPN and PNP transistors can't be used to switch AC?

An NPN transistor is normally biased with the collector biased positive with respect to the emitter. It is turned on by a voltage on the base, which is also positive with respect to the emitter. A PNP transistor works just the opposite with the base and collector biased negatively with respect to the emitter. You have suggested putting them in PARALLEL.

Given the above, what is the likelyhood of THAT working ? What does that say about your electronics experience ?

Post a schematic of what you suggesting .

Thanks to all to answer. Actually I want to switch more than 10 devices that fed with 220v AC and also the size of my pcb is about 7*10 cm . I think I don't have any way except using relay. Thanks again.

Do you know how to drive the relays? Not directly from the Arduino pins.

You can fit many relays on a 7x10cm board.
Use 2 daisychained shift registers and drive up to 16 of them. Here’s 8 of them for example.

or buy it ready made: http://www.ebay.com/itm/8-Channel-5V-Relay-Shield-Module-Board-Optocoupler-module-Arduino-ARM-PIC-AVR-/161317483666?hash=item258f457492

..... I couldn't even buy the relays for that.

Actually I want to switch more than 10 devices that fed with 220v AC

You didn’t say whether you needed to switch them individually or simultaneously.

Single 5V Relay Module