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Mark Rosenbaum 09-26-2019 11:10 AM

Electrical Question
I am not an electrician, and I don't pretend to be.
I was gifted a large annealer. It has regular elements around the sides, and a "supercharge" element on top that is separate so that you can turn it on for fusing or slumping. I have no idea how much draw that the elements will take, and neither does the person I got it from. It has never been there a way to measure what the amp draw will be? I don't want to have everything wired to find out that I am short.... TIA

Rick Wilton 09-26-2019 11:32 AM

I would "jerry rig" it up and put a amperage clamp on the wires to determine the amp draw.

Pete VanderLaan 09-26-2019 12:51 PM

Most commercial elements will run at about 12 AMPS if they are wire elements. That's likely of the top one as well. Rick is spot on with measuring the draw on each one.
Three elements typically will run under a 50 AMP breaker and likely under a 45 AMP one. Do pay attention to the connections between the elements, any limiting control and the service iwre feeding the thing. I would use a fiberglaass wrapped 10 gauge wire to make the connections along with split bolts. Don't rely on wire nuts. I have purchased the high temp wire on Amazon.

Sky Campbell 09-26-2019 01:05 PM

Use ohms law. Plug in the resistance and voltage to determine amperage.

Sky Campbell 09-26-2019 01:08 PM

This is one of the greatest resources on heating elements for our applications.

If you donít understand ohms law google ohms law calculator and punch in the known variables to get your answer.

Eben Horton 09-26-2019 02:00 PM

Work backwards. Do the math and calculate the volume of the annealer and the required amps to make it work.

I have 3 14 amp elements in my annealer ( 3360 watts)

Art Freas 09-26-2019 02:16 PM

IF, note IF, it is built right the plug should give you a rough idea (if it has a plug). Plug configuration is specific to a phase, amp, and volt configuration.

Shawn Everette 09-26-2019 03:03 PM

Pics please. We're flying a little blind here.

Sky is correct on ohm's law, but without it being a commercial kiln, or knowing the approximate volume, it's hard to say if it's going under or over powered. Especially having never be fired.

Phase configuration and your voltage will come into play as well.

With inherited homebrew always assume it's under powered AND wired wrong.

Rich Simmons 09-26-2019 03:05 PM

2 Attachment(s)
I happen to be doing something very similar to Mark. I was gifted a large annealer that I'm rebuilding also. I had planned to replace the Omega controller on the thing once I knew everything is functional as is. My question is related to a separate plug (120v) for the controller. The design follows almost exactly Dudley's circuit shown here:

Attachment 5792

My annealer has two plugs 120v for the controller and 240v for the elements. I assume this design was to incorporate the distance between the controller and the lehr. Is there any reason you know of, not to just tap the neutral from the 240v plug across one of the hot (in this case Red wire)?

My thought:
Attachment 5793

Am I missing something?

Brian Graham 09-26-2019 03:16 PM

I have done what you just described Rich and it will work - as long as there is a path to the ground / neutral in the panel. I recommend keeping them isolated though. If something gets shorted and messed up in your 240 circuit - it could fry your 120 devices in the process. I also protect all of my components with quick blow semiconductor fuses.

Rich Simmons 09-27-2019 10:53 AM

Thanks for the advice Brian!
I'll keep them separate.
I checked and there are no fuses. I'll add one.

Richard Huntrods 09-27-2019 12:26 PM

My furnace and annealer are both 240V and the controller (Fuji) runs on 110. I did exactly that with both - use a 120 leg to run the controller and the 240 to run the wires. Single 240 plug to the wall. It's been that way since 2003.

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