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Hi,
I'm making a bending iron out of aluminum pipe, a charcoal starter, and a 600 watt, single pole rotary dimmer. What I am doing is wiring the charcoal starter in line with the dimmer switch, and with a power cable that then goes to a power outlet when needed.
The wires coming from the dimmer are green (ground), and two black.
The wires on the charcoal starter, and the 3 prong plug I'm connecting to, are green, white and black.
I have wired them every way I can. I've joined both white wires and connected them to a black, then joined the other black and green wires to their respective colors. I've switched the white wires to the other black, I've wired a white to a black, and the other white to the other black. The only thing I haven't done is connect the green ground wires to one of the other colors, and I don't think that's a good idea.
I get power either way I wire, and the charcoal starter and the pipe heat up. But the dimmer is set up so you can psh it to turn on and off. That function does not work no matter how I wire it, and the dimmer switch does not control the temp; it is full on no matter what I do.
Can anyone help me?

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Mike,
I'm not an electrician by trade, but I've done my own wiring for almost a decade. So take this for what it is.

In a a 110v system, you have hot, neutral, and ground. Your dimmer switch has a ground and two hot wires- one in and one out. Your charcoal starter has a hot, neutral, and ground... if I'm understanding the system correctly.

A switch operates by interrupting the hot line (black). Ground and neutral pass by the switch though ground is typically tied to it for safety reasons.

So in your system, connect a black wire from power to one black wire on the switch and a black wire from the starter to the other black wire on the switch. Nut all the neutrals (2) together and nut all the grounds (3) together- including the one on the switch. This should all be done inside a conduit box with properly sized wire for the amperage load it'll carrying according to your local code.

Hope this helps (and is correct). If I'm wrong... this message never happened!

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ELEVATE || Next Level Lutherie
http://elevatelutherie.com
&
http://ensorguitars.com

That sounds right. I thought it was something I was doing wrongwith the neutral wires. I will give that a go. Thanks!

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Not to complicate matters but. . . you might consider adding in a hot tub timer switch inline too. I did on mine because it is easy to get side tracked and forget to turn it off.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

My first question would be what is the draw on the charcoal starter? Those 600W rotary dimmers usually fail long before a load of 600W is applied.

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Julie Moriarty
http://JulimorCreations.com

That's correct.

At the dimmer:
The green is a ground wire, not a neural. Connect it to the green to the plug and the green to the charcoal starter, use a screw cap
One of the blacks, it doesn't matter which one, connect to the black going to the plug
The other black connects to the black to the char lighter

The white from the plug, this is the nuetral, connects to the white to the char lighter. Use a screw cap.

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Joe Beaver
Maker of Sawdust

I don't remember what my charcoal starter is but I know I checked it before I settled on the dimmer switch. I do know that my blanket is 540 watts, I run it through the same set-up and have had no problem in the 6 or so years I have been using it. I will say that I rarely run it wide open though.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Thanks, gentlemen,
I have it wired per Bryan's post. The starter is getting hot, but very slowly, with the dimmer wide open. I can still wrap my hand around it after 10 minutes or so, and the element hasn't begun to glow. I had to stop because of rain(outdoors). Should it take this long to heat up?

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Sounds like something is wrong. It should heat up pretty quickly.

I'd guess you have a faulty dimmer switch or a faulty char lighter.

The easiest way to find out is with a voltmeter if you have one. Just check the output voltage from the dimmer at various settings. It should go from 0 to near 120V as you turn the dimmer up. If it does and your wiring is correct then the char lighter is bad. (just be sure to check voltage between the black output wire from the dimmer and the white ground wire from the plug, not the green ground.)

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Joe Beaver
Maker of Sawdust

Joe, thanks.
The element is good. If I wire straight to the power cord from the charcoal starter it glows cherry red in less than a minute.
I'll check with a meter, but I suck using one.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

One thing to keep in mind with a single pole wall switch, dimmer or otherwise, is that it only switches the hot (Black or red wire). So you have a source hot wire going to the switch and a switched hot wire going out of it. It doesn't deal at all with the neutral. The only exception is a switch that has an on/off indicator light, A neutral goes to it just for the indicator light to work. You still have to connect the white wire direct to the appliance.

If a person was to rely on the green wire, and no white neutral going to appliance they might experience unsteady/low voltage causing problems.

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Joe Beaver
Maker of Sawdust

I'm now confused. Are you saying that I should have the white connected to the green ground at the dimmer?
Please forgive me. This should be a very simple wiring job, like wiring my fan up in my ceiling, etc. I don't understand why I cannot grasp it. Thanks for everyone's help.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Let me make a sketch. I'll post it in a few minutes

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Joe Beaver
Maker of Sawdust

thank you

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Diagram (crude as it it)

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Joe Beaver
Maker of Sawdust

Joe, thanks. That is exactly how I have it wired. I know the starter is good, so, I expect the dimmer is toast. I'll go get the router speed control at Harbor Freight. Thanks for your time and patience. I really do appreciate it.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

600w dimmers are pricey, maybe a return is in order

Edit: I was thinking of a 1200w. Julie is most likely right. A charcoal lighter can quickly toast a standard 600w dimmer.

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Joe Beaver
Maker of Sawdust

I have wired this about 4 different ways, maybe five. The first time I wired it up, when I plugged it in, it sparked at the outlet. I checked that the breaker wasn't tripped, and thought no more of it. I think I fried it the first time I plugged it in, and have been working with a dead dimmer the whole time.
I might grab another here locally at Lowes, and wire it up correctly this time; see how that works. Worth a try before I run in to Winchester for the router control. If that fails, I will pick up the router speed control when I can.
I have what I think is a bad hub bearing in my vehicle. I just replaced the front left axle, now this. Can't make that trip just yet. Lowes is three miles away.
Dimmer is $8-$9.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Thanks to everyone who posted in this thread.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Having replaced more rotary dimmers than I care to remember, I think that kind of dimmer is not the right choice for controlling anything more than a few light bulbs. I've seen them fail with as little as 300 watts of load. A rotary dimmer dims a light by adding resistance to the feed. The charcoal starter heats through resistance. Resistance creates heat and heat breaks down devices over time. Best bet is to find a different controller than a rotary dimmer unless you are sure you have figured all the loads correctly and they don't exceed something like 50% of the rating of the dimmer.

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Julie Moriarty
http://JulimorCreations.com

Most rotary dimmers these days are thyristor devices (semiconductors), not resistor devices. They will almost certainly fail if wired incorrectly. They also have to be of the correct type for the device being dimmed. Incandescent globes and charcoal starters are both resistive elements so a charcoal starter should work fine with a dimmer for incandescent lights. You then have the rating issue. Most incandescent loads pull a high current on start up due to being cold. Resistance then increases rapidly with temperature. So startup power can be instantaneously very high, plenty more than the load's "run" rating, sufficient to blow a dimmer with a "run" rating the same as the load run rating. Round here we don't have to worry about that, though, because it seems our electrical standards ensure that a 500w dimmer will work with the correct type of 500w load, i.e spec'd by default to live through the start transient.

The book has a section on making side bending pipes. Rather than use a charcoal starter, I used a 500w linear tungsten globe as used in flood lights. I used the ceramic globe holders from an old flood light and mounted them and the globe in a section of aluminium yacht mast. Mine's being going with the same globe and dimmer for nearly 20 years now. I use the same dimmer on a small diameter pipe that I use for bending Venetian cutaways. The heaters in that are a couple of 1kW bars from a radiant heater, wired in series to bring the power down to 500w.

Dimmer and bender using the linear halogen globe:


Cutaway bender using radiant heater bars:


I have a timer on a wall socket and all my benders (I have more!) plug into that.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

If it sparked when you plugged it in, you had a short.....probably across the dimmer. In other words, you had the dimmer wired in parallel instead of in series with the charcoal starter.

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John

I got a router speed controller which was said to be better. I stopped using it as my charcoal starter was fine wide open. Spray water to cool it down.

This one might be as well. Since I've never done it, it's hard to tell. But when I hit it with a spray of water from a spray bottle, it instantly turns to steam, lol.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Mike.

A router controller is really what you need here if you want a variable control.

But - Bob brings up a fantastic point. Try it wide open first to see how it goes. You will likely find it's fine...

Personally - I find side bending is much easier hotter and faster than cooler/slower.