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  1. #21
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    Maybe this diagram will help. Many power supplies are more universal so accept a wider range of input voltage like 100-240 VAC. In machine applications with VFD's where I have set them up to run single phase or three phase, I connect the power supply between two of the input 3 phase. If the power supply requires 120VAC I will use a neutral (when wired as such) and one phase Y configuration. Alternative would be to use a 120VAC output step down transformer between any of the the two legs of the 3 phase which is the most common.
    TB-69301 - Acme Electric - General Purpose Transformers | Galco Industrial Electronics
    Attachment 265131

  2. #22
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    I know nothing about European power but you are probably correct that their power consists of a hot let and a neutral.

    Wall warts have to be make to safety standards and I am sure that would include faults like ungrounded neutral, reversed wiring to the outlet, etc. I do not believe that the wall wart cares if one lead is grounded (thats what a neutral is) or if one is grounded, which one it is. In any case it will see 240 volts between the two input wires and that is what it needs to operate. Most walwarts have an unpolarized plug with no ground pin. This means they can be plugged in any which way with out concern.

  3. #23
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    Instead of a control transformer, fusing, an outlet and a wall wart switch mode power supply, you might consider a switch mode power supply, 240VAC to 5VDC, intended for a control panel. Likely to be smaller, neater, and cheaper. And can contain built in overload protection.

    csw65-1128541.jpg

    Here's a link for a data sheet of one such unit.
    https://www.mouser.com/datasheet/2/4...65-1128541.pdf

    Product page.
    https://www.mouser.com/ProductDetail...KtAW6xhQ%3D%3D

    A dirt cheap import one that doesn't have any testing agency listings, and may be of questionable quality.

    Switch Power Supply Adapter AC100-240V to DC 5V 4A 20W Voltage Transformer AC-DC | eBay

    You could use the cable and molded connector from your wall wart, if it will reach inside the panel, but a purpose fabricated cable would be better.

    Wiring a 120V outlet, at 230V, to use a 120V pronged wall wart, at 230V is not a good idea.

    If there is a next time, you may be able to order a DRO with a 230V configured wall wart, and obtain a matching outlet to install.

    SAF Ω

  4. #24
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    Seems to be a whole lotta complexity here for such a simple problem.

    Bring two of your 3 incoming legs (somewhere downstream of the main power switch) to the primary side of a 240:120 control transformer... 100va would be enough.

    Connect the secondary to a receptacle suitable for the wall wart. Plug your 7w LED machine lamp in the other.

    Power switch on, DRO comes on, light comes on.


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