Grounding wires

[Ron Boyd]

I've seen several topics with DIY kits and using SPT-1 and SPT-2 wire for dongles. My question is about grounding. On the controllers where I have plugged in the dongles and power cords, Black goes to the channel post, White to the neutral posts and green to the strain relief posts.

If I use SPT-2 and I plug the hot side to channels and cold side to neutrals, do I not need to ground the dongles? If not, do I have to ground the box/enclosure some way.

Thanks for the help

[Dave Batzdorf]

95% of the items that you'll plug in only have the two wires anyway. Therefore no, you dont really need the ground for the dongles, unless you are using a three wire extension cord. Then I would recommend the three wire dongle just so you dont have to use a 2-3 wire adapter.

[Guest guest]

Even most of the "motorized" props I've bought only have a polarized 2 prong plug on the motor. (Wireframe Black Cat & Spider for Halloween, Wireframe Deer for Christmas}.

Rarely have I ever come across one with a 3 wire prong {Grounded} plug.

So I think you're fine with a 2 prong plug, just make sure that every one is wired exactly alike or you might have some issues if one {or more} happens to be reversed from the others. If you use a GFCI{highly recommended}, you may get more trips than you bargained for if all the cords aren't wired the same exact way under some weather conditions where lights and props get a little damp or wet{rain, sprinkler system}.

EDIT - Please take note: the large prong side {if applicable} should go to the Neutral side {White wire}, the small prong side should go to the Hot {Black wire}.

[Ron Boyd]

That's what I thought, I just wanted to make sure. Thanks Guys.

[-klb-]

The one case where I would strongly urge a ground is if you have a metal case, or if the heat sinks are mounted with hardware that penetrates the case.

Generally when a triac fails, it remains isolated from the heat sink. But occasionally, it will short through to the heat sink. If this happens with the heat sink bolted to a metal case, or with hardware extending through, you now have an electrocution hazard. On the other hand, if it happens, and the heat sink, or metal case is grounded, it should trip the breaker instead.

[Guest guest]

-klb- wrote:

The one case where I would strongly urge a ground is if you have a metal case, or if the heat sinks are mounted with hardware that penetrates the case.

Generally when a triac fails, it remains isolated from the heat sink. But occasionally, it will short through to the heat sink. If this happens with the heat sink bolted to a metal case, or with hardware extending through, you now have an electrocution hazard. On the other hand, if it happens, and the heat sink, or metal case is grounded, it should trip the breaker instead.

Good point klb! I use the CTB16PC's in the plastic case, so I sometimes forget about the commercial versions that are in a metal case. Thanks for the reminder!

Always better to be safe now than sorry later!

[Ron Boyd]

100% check ok on my second attempt to solder a kit. I haven't tested my first one yet.I had to de-solder (first attempt too) some stuff on it and get some new resistors, so I want to make sure everything's ok first.

[TitusCarnathan]

I would still recommend grouding it for peace of mind Just use the Regular Grounded Extenstion cords for the Main also spt1 and 2 is only rated for about 7 amps I would say you would be better off with the better cord just for the main power feed to the controller but spt1 and 2 to the lights is fine since you would probably be pulling less than 7 per channel

[Ron Boyd]

For the main power into controller, I used SJOOW, (I think) 14 gauge and a 3 prong plug. SPT-2 and vampire plugs for the outputs. I've already tested half of the lights that will be on the controller with my Kill-A-Watt and it was a total of .16 amps for the arch. (.02 amps per channel) As a matter of fact, I e-mailed the folks over at Holiday Light Express. Their reply was 0.02 amps per string for the 70 ct. LEDs I got from them. That's only .32 amps per controller x 3