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enter image description here[![enter image description here][2]][2]heat press electrical

I purchased a heat press that was supposed to be 220 V, 3-phase, but 380 V showed up. It is 12 kW, 32 A, no moving parts or motors. It came from overseas so returning it not an option, and the seller is not much help.

It's a big heavy press with a plate for pressing custom sublimation images, no different from a t-shirt heat press, just much larger.

Anyway, when I measure my line 1, 2 and 3 at the contactor it's very unbalanced: 45 A, 35 A, and 15 A.

I don't know how to make it work. Can I make it 220 V? Or should I buy a transformer? I have no clue where the transformer would sit, nor do I know what kind of transformer to buy.

Is there a way to balance the lines, as one of them just burnt recently?

Attached is an image of my electrical box. At the very bottom comes my power. L1, L2, and L3 (no neutral) go to a box with a fuse, then to a contactor. The contactor has 3 lines, but initially one port had 2 wires together and I took one out (red thicker gauge you see with electric tape) as it burnt. From the contactor it attaches outside to the plate that heats up. The rest of the stuff is just a timer, temperature setting, kill switch, power button, and a temperature thermocouple.

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    \$\begingroup\$ wait, this isn't the confusion between 220 V amplitude and \$\sqrt 3\cdot 220\$ voltage between phases? \$\endgroup\$
    – Marcus Müller
    Commented Jan 21, 2023 at 13:32
  • \$\begingroup\$ This looks home made to me and, potentially dangerous from what you describe. I'd get an electrical company local to yourself to take a look at it. By the sounds of it, you are not qualified to make wiring changes to it. Is there no incoming earth wire? \$\endgroup\$
    – Andy aka
    Commented Jan 21, 2023 at 13:32
  • \$\begingroup\$ Denominations like 230/400 V (220/380 V in times gone by) may refer to the same thing: 230 V life to neutral, 400 V between any two phases. \$\endgroup\$
    – greybeard
    Commented Jan 21, 2023 at 13:33
  • \$\begingroup\$ @greybeard well not adventurous. Vendor recommended to add extra line. The contraption is working, my heat at the platen is distributed evenly and I can continue working. \$\endgroup\$
    – Ben Jelic
    Commented Jan 21, 2023 at 15:28
  • \$\begingroup\$ You should provide a schematic as well as specifications, or at least a link to the product page where you bought it. Is this actually a temperature controller? What are the controls on the left? Looks like maybe start/stop and perhaps a temperature or time setting. (edit) I do see a temperature gauge on the top left. \$\endgroup\$
    – PStechPaul
    Commented Jan 21, 2023 at 15:43

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The photo you show is just a borderline-dangerous rat's nest of contactors, breakers, terminals and so on, shoved into a box which is much too small for its contents.

There is nothing in here to transform voltages. The voltage you get out will be the voltage you put in. Possibilities in what you're seeing:

  1. Everything is actually fine (apart from the really poor panel-building work) and you are measuring interphase or peak-to-peak voltage;

  2. Your load is single-phase and for some reason you are presenting two phases at each of its live terminals rather than line and neutral, either a misunderstanding by you or the panel-maker as to the correct wiring;

  3. There's something wrong with the neutral in your installation (independent of your panel).

  4. If any of the loads are motors (it sounds like they are mainly heaters), there's been some miscommunication on Y/Δ configuration.

This project needs some on-site work by people who have at least electrical qualifications, both at the panel-building and installation-and-commissioning stage, or it is going to limp on from one confusion to the next.

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    \$\begingroup\$ Alright so now I understand it’s a dangerous box. I will attempt to find new qualified faces to look at my machine. That was my initial approach but could find the right help. Thanks! \$\endgroup\$
    – Ben Jelic
    Commented Jan 21, 2023 at 15:34
  • \$\begingroup\$ @ Dannie can I ask you one more thing please. I have been using the machine like this for several years. It’s working. I will get someone in to look at it, if I can find someone as I don’t live in a big city. Will a transformer help me with the imbalanced phases? Is that imbalance for to machine result that machine is 380 v or it’s not related? Lastly, is neutral not necessary in 3 phase? Thanks. \$\endgroup\$
    – Ben Jelic
    Commented Jan 21, 2023 at 20:07
  • \$\begingroup\$ @BenJelic In a three phase system, there are various voltages depending what and how you measure (which wires, what kind of measurement, etc). I don't know all the details of your setup, I would very strongly suspect that what you are seeing is due to a simple miswiring, or a mismeasurement on your part, (or perhaps a somehow-different load) in this new case. That's good news in a way. What will probably happen is someone comes in, asks you lots of questions, looks at a working version, looks draws out some schematics, makes some measurements and then ... swaps two wires around (or similar). \$\endgroup\$
    – Dannie
    Commented Jan 22, 2023 at 13:36
  • \$\begingroup\$ @BenJelic It was a good thought to post it here, but it's the kind of thing where there are far too many possibilities and uncertainties in the system that I don't think anyone would be able to tell you from photos. If the panel had been laid out more cleanly that would have helped a little, but probably not enough. \$\endgroup\$
    – Dannie
    Commented Jan 22, 2023 at 13:39
  • \$\begingroup\$ @BenJelic In terms of phase imbalance this is something caused either by faulty equipment somewhere in your factory (or perhaps even next door!) ,or too many single-phase loads on one phase., or a bad neutral It could be this machine or any other machine, or the machines altogether, or a fault in a distribution board. If this box is connected to a "good" load (a not broken heater etc) and wired per your schematic this box cannot cause a phase imbalance in itself Your box is simply sends on all three phases, or not, depending on some fused, very low current interlocking on phase three. \$\endgroup\$
    – Dannie
    Commented Jan 22, 2023 at 14:00

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