Name that TDB. To the Electrical Experts amongst us, what is the proper name for the item listed as TBD? And what is its function? Also, the item mentioned above (the heat exchanger), what is it called? Obvious it gets rid of heat, but any idea what electrical device is inside of it that requires it to need the heat exchanger?
I believe the two others are inductor coils
The water cooled âinductor blockâ looks to me like a water cooled step down transformer with multiple high side taps, likely being used as coupling transformer. The âtbdâ array of 8 black boxes is likely 8 high power capacitors, as the induction coil is usually a RLC tank circuit, where you try to keep a lot of energy bouncing back and forth through the induction coil alternating the polarity of the charge on these caps. The coupling transformer is taking the high (likely relatively) voltage, low current drive, and creating a low voltage, high current drive to push that current to oscillate back and forth in the RLC tank, and supply the power that goes into heating and losses.
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So I stopped by this morning, the heating induction coil it clear. While sitting around today waiting for my vehicle to be serviced, I had some more thoughts. Iâm here now at the space, & was looking at the piping. It dawned on me that the pump we are using probably doesnât meet the requirements for the casting machine. So I look through the spec to see 30-45 psid at 80 liters an hour. I donât believe the pump we were using to test would get this high. The pump at a minimum would have to be rated for 70ft of head. So either we can use some water hoses(very temporary) or another pump to test it.
I would be inclined to go with the hose test assuming the 35 quart bucket is still there⌠Another idea would be to check the flow sensor to see if it is working. I donât know if it is a Normally Closed or Normally Open switch; I wouldnât think it is more than that(?).
So we have more progress. I donât want to take it any further with any kind of load in it. I temporarily tied in the TIG cooler from the nonfunctional at the moment, TIG machine.
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Anyone want to schedule a time to give this thing a better test? In the meantime I will put things back the way they were including the TIG cooler. Unless someone wants to come by in the next hour or so.
We tried this with the sump pump previously and had decent water flow. Is there Pressure sensor perhaps?
Iâm assuming that the flow switch is a paddle type. I havenât looked at it close enough to see if it was a thermal dispersion or paddle. Pressure switch would have to be a differential switch to know if you had flow.
I would say the heating portion works. No doubt in my mind as it heated up some steel stock in a matter of seconds. Hot enough to turn it blue, yes in a matter of a few seconds.
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Awesome! Its working and I wired up that plug correctly 
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This is great newsâŚThank you @TBJK for taking the time to troubleshoot this, I really appreciate it!
Did you happen to see if it would spin? How should we plan to set up the water cooling system long term?
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I didnât try to spin it, just make sure the heating worked. I figured we needed to get a crucible & flask in it to try to spin/balance it. If we find a different pump then we could try that. For us to do an âofficial full function testâ we can temporarily tie the TIG cooler in again. I think that should be our next step. Also when I turn the dial up, you can see the analog gauge in the back of the machine linearly move. I donât even think we need to do it with platinum either, I think we could use a lower melt metal.
Ideally we donât have anything to loose by trying it.
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I would love to be able to melt copper, not enought scrap to seel but I
hate to pitch it also !
Got it. I have ordered a crucible and should have it next week for a test run.
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Yes!!! Whahoo!!! 
What is the capacity of material that can be melted?
120 grams. There is a larger 300g crucible but it is $100+. I received the 120g one on Saturday.
All we need to do now is find a way to secure the flasks. The flasks we have donât exactly fit. I am sure someone can figure out a saddle or some type of support for the small 2x3 flask. Once we have that, we are ready for a test cast.
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We can fabricate a strap to secure the flask.
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I think we are on track to get this thing up and running! Thank you all that have been involved to help make it happen!!
The water pump @David_Steele and container @jphelps that was provided for testing can be picked up now. Thanks for letting us borrow!
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