Will this work for switching 110V mini christmas lights on and off safely?

[jarrodhroberson]

I have not been able to find any definitive independent documentation that the relay on this board will not burn my house down.

http://www.ebay.com/itm/New-1Channel-5V-Relay-Expansion-Board-Module-High-Level-Triger-for-Arduino-MSYG-/171666166850

It uses a SRD-5VDC-SL-C SONGLE which I can only really find any specs on in Chinese.

It claims Rated load: 10A 250VAC/28VDC,10A 125VAC/28VDC,10A 125VAC/28VDC

My plan is to replace all the timers that my wife puts on the lights on the wreaths that she hangs on the windows every year with a ATtiny/433mhz powered wireless receiver and one of these relays.

Will this actual switch US 110VAC safely? I know the lights are no where near 10A.

Then I can have one 433mhz transmitter trigger all the lights to go on and off at the same time instead of having to synchronize all these timers on each outlet.

[Paul Moir]

The c RU us symbol on the top is a combination CSA & UL recognition mark, so that's a real good sign.  What they did on the PCB is a big question though.

However, I would say where minilights are concerned, if you put a fuse on the whole thing set nice and low you would be *way* out ahead in the not-burning-your-house-down factor.  I mean we get all concerned about clearances and ratings here, but what's really likely with them is to get a good arc going in the wires themselves from damaged insulation.

[jarrodhroberson]

Thanks for the reply, all the light strands have fuses build into the 110 plug on them now, so that should take care of that.

[Richard Crowley]

They are so cheap it would be worth buying a 5-pack just on speculation.  I agree with Mr. Moir that it somewhat depends on how well they designed the PC board unerneath. But I would have high expectations that it would safely handle modest loads like mini-Christmas light strings.

[jarrodhroberson]

This one has a nice slot designed into it so I think I will get it and try it.

[eneuro]

Does it has some kind of softstart feature or this switch is too slow?

Anyway  too  many China characters on this board 

[Richard Crowley]

Yes, that example looks reasonably good.
My major complaint would be that it has no provision for mechanical mounting (like a couple of screw holes, etc.)
Do they think people will just let these things flop around in the breeze, "secured" only by the connected wires?

[Ian.M]

Its also mechanically weak as the notched out area is approx 1/3 the width of the board.   

Q. Would I use it for switching an amp or two at 12 or 24 V?
A. Probably if I had it handy + some foam VHB tape to mount it.

Q. Would I use it for >3A or >50V?
A. H**l No.  There is absolutely no way to mount it safely short of a custom moulded plastic mounting base.

[eneuro]

Sometimes it is difficult to buy cheap PCB with good connectors, so I have my own footprint for such much more powerfull connectors 3mm inner diameter and 7mm outer ring secured with spring washer and submerged in non-conductive substance - hot glued
Those connectors looks like those 24VAC transformer inputs below-not submerged yet, ready for testing after soldering this simple prototype +/-12VDC PSU for AC mosfets switch:

Of course it require a little effort to make proper wires, but it is better sometimes have something with label "Made  at Home" "NOT IN CHINA"