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How do I use 5VDC to switch 120VAC?

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I'm using an Arduino that can output 5VDC and 40mA.
Is that per output pin, or the total for all output pins?
As you plan on switching 4 lamps independently, make sure that, if 4 lamps are 'on' simultaneously, the Arduino's maximum output power rating is not exceeded.
 
Is that per output pin, or the total for all output pins?

Good point. I had checked this issue but forgot to mention it. It is (surprisingly) ±40mA per pin. The datasheet mentions a limit of 150mA for certain group of pins.

But for the op, 4 × -20mA shouldn't be a problem.
 
Make sure you wire the AC side exactly per the data sheet example(s).

Ron

You are referring to the snubber circuit and fuse that the datasheet indicates I should include, correct? I am planning on just finding 2A fuses, since the SSRs are only rated to 2A.

However I'm not sure what I should use for the snubber circuit. From what I've read, snubber circuits are simply a resistor and a capacitor, and snubbers are a resistor and a capacitor in one component? How are snubbers rated? I'm guessing they at least have a maximum current rating.
Additionally, I tried looking for snubbers on Mouser and Digikey, but I can't find a category for them. Are snubbers typically called something else? I know that varistors and TVSs are other means of circuit protection, can they be used as substitutes for a snubber?

Thanks everyone
 
You are referring to the snubber circuit and fuse that the datasheet indicates I should include, correct? I am planning on just finding 2A fuses, since the SSRs are only rated to 2A.

However I'm not sure what I should use for the snubber circuit. From what I've read, snubber circuits are simply a resistor and a capacitor, and snubbers are a resistor and a capacitor in one component? How are snubbers rated? I'm guessing they at least have a maximum current rating.
Additionally, I tried looking for snubbers on Mouser and Digikey, but I can't find a category for them. Are snubbers typically called something else? I know that varistors and TVSs are other means of circuit protection, can they be used as substitutes for a snubber?

Thanks everyone

Actually I was more getting at placing your load on the correct pin. :)

This is your data sheet and if we look at page 9 they show the connections.

Now if you were running a motor or other inductive device then I would worry about a snubber. However, as long as the subject arose this is a good read on RC snubber circuits. Since you will be driving incandescent lamps I wouldn't worry about a snubber.

Also, while looking at the drawing, the diode you see at the control input is just there for reverse polarity protection any 1N4001 or 1N4002 would work fine or similar diode, if you choose to use one.

Oh yeah, also if you go to DigiKey and search Quencharc you should get this page which has the same units I linked to.

Ron
 
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Thanks Ron.

Well it looks like using a snubber is not necessary and using a diode is optional. Would you still recommend using a fuse, or do you think I can get away with not using fuses? I think I will, because I think protection of my electronics is worth the extra few dollars.
 
Fuses are cheap at the price. :)

Ron
 
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