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Ok guy this weekend I picked up very old kiln, it is about 18in high and 24in wide inside. It has elements on the bottom and sides. It has an old pyro-meter VU meter style, and is 220v. The issue I have is the 220v, we rent and unplugging the dryer every time will end up driving my wife crazy. Since this is a small kiln can this be switched over to 120v? I need to update the controller anyway, the bottom element are not needed for what I do, mostly glass casting and fusing. Let me know if this is possible, thanks!!!

No, not really. You can expect a kiln that size to draw about 30 amps at 240 volts or 7200 watts. Thats about 1500 Watts/cubic ft for your kiln. Even the most efficient kilns use about 800 Watts/cubic foot which gets you down to about 16 Amps at 240 volts. You're still talking about rewiring power to do that, so you might as well hire an electrician to install another dryer circuit and outlet.

Tony Smith wrote:No, not really. You can expect a kiln that size to draw about 30 amps at 240 volts or 7200 watts. Thats about 1500 Watts/cubic ft for your kiln. Even the most efficient kilns use about 800 Watts/cubic foot which gets you down to about 16 Amps at 240 volts. You're still talking about rewiring power to do that, so you might as well hire an electrician to install another dryer circuit and outlet.

Thanks I was hoping.

Why do companies sell you and infinite switch, however when you go to buy one it is parts and not a complete unit where you plug your heating
elements in and your done. I figured I would update the controller, cannot afford a digital at this time.

I'm not sure what you're asking. Infinite switches usually come as a switch block with push-on spade lugs on the back. Sometimes you can get them with a knob and indicator bezel as well.

Tony

Tony Smith wrote:I'm not sure what you're asking. Infinite switches usually come as a switch block with push-on spade lugs on the back. Sometimes you can get them with a knob and indicator bezel as well.

Tony

Sorry I am Computer tech I expect everything to be plug-n-play. I was looking for complete units with switch, relay, and power cord. All you would have to do is add your elements. and you would be done.

BTW it is a NORMAN Electric Kiln mfg 1983- GS 918 - phase 1- 220 v - 18 amps

I've never seen an infinite switch used with a relay. Is that how the Norman is set up?

Tony

Tony Smith wrote:I've never seen an infinite switch used with a relay. Is that how the Norman is set up?

Tony

I was looking at the DIY kits for the digital controller i thought it was more complicated then just a switch. Finally got the controller off and open, they built these like a tank BTW. I do have a question, the plug is an old 3 prong 220, my outlet is 4, when I swapped the dryer and oven cords out it had me ground to the chassis. Just making sure that I do nothing different will the kiln, just ground it to the box, correct. Thanks for all your help!!!

A three prong dryer cord ties the neutral directly to the chassis ground.

Tony

Tony Smith wrote:A three prong dryer cord ties the neutral directly to the chassis ground.

Tony

Correct.

The 4 prong is now the updated code here. 2 hot 1 neutral 1 ground.
I have read many things connect the hots then....
1 - take the neutral and ground and connect to the chassis
2 - Leave off the neutral, it is used for 110v appliance may have need for it, and use the ground only.

Just want to make sure.

Sorry. I misunderstood the question.

With a four-wire cord, you have two hots, a neutral and a ground.
Connect the two hot leads to the same places the hot leads connected to with the three wire cord. Connect the neutral to where the third wire on the three-wire cord connected to and connect the ground to the chassis. You can break the old connection between the neutral and the chassis if there is one.

Tony