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The old fashioned way to configure a lot of boards is to use pin headers with their jumper cap, i.e.:

https://www.tme.eu/en/details/jumper-kpl/pin-headers/connfly/ds1027-01-2ab801/

enter image description here

On my board I need something similar to configure a high-power power source. Basically I have three screw connectors, and the user needs to select which one to use to power the driver. To be clear:

schematic

simulate this circuit – Schematic created using CircuitLab

The three power sources are rated:

  • 24V 4A
  • 48V 6A
  • 60V 8A

Obviously I cannot use the tiny headers like above. Well, I can put several of them in parallel but it's an ugly solution and error prone. And the customer doesn't want a solder jumper.

I searched with keywords like "high power jumpers" but I found nothing - at least nothing useful to use on a PCB.

Does this kind of high current jumpers exist? How are they called?

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    \$\begingroup\$ They are called fuses. Fit 3 fuseholders and supply one 8A fuse (well OK maybe a spare too. It won't protect against pathological users plugging in the spare,, but neither will jumpers). \$\endgroup\$ May 15 at 11:23
  • \$\begingroup\$ You could use relays (and close the circuit through their coil with the small jumpers), though I like @user_1818839's suggestion of fuses in fuseholders. \$\endgroup\$
    – Hearth
    May 15 at 12:42
  • \$\begingroup\$ @user_1818839, it's a good hint. \$\endgroup\$
    – Mark
    May 15 at 14:03
  • \$\begingroup\$ @Hearth, I don't like this solution too much. The relay is good for something that has to be disconnected sooner or later. Here the set up it's final. Anyway, thanks for the idea! \$\endgroup\$
    – Mark
    May 15 at 14:05
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    \$\begingroup\$ @Kyle B, That is a good solution, but I would go for a part that is rated more than 60V Vds, just in case. Mind the power dissipation at 8A continuous if that might be a possibility, and maximum Vgs is seldom much above 20V. This part might be a better fit; nz.mouser.com/ProductDetail/Vishay-Siliconix/… \$\endgroup\$
    – Gwyn
    May 16 at 0:49
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This is how we did it when I worked for a company that made large SCR phase control units:

enter image description here

https://www.digikey.com/en/products/detail/nte-electronics-inc/25-B500-03/11651152 https://www.digikey.com/en/products/detail/molex/0380020188/3185363

This is for mounting on a panel. You can probably find something similar for a PCB.

I just found these quickly, no guarantee that they are compatible with each other.

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Will exactly one of the three sources always be used ? i.e., zero sources and two sources situation is not expected to be configured ?

If so, a foolproof method is to use single pole three throw switch. That way, user cannot connect two sources at the same time by mistake.

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  • \$\begingroup\$ Yes, always exactly one of the three sources has to be used. If there is a small PCB single-pole three-throw switch that is capable of handle such currents and voltages it may fit. Would you please link an example of a component you had in mind? \$\endgroup\$
    – Mark
    May 15 at 14:07
  • \$\begingroup\$ I have not used one myself. I have only seen in products. I wouldn't be able to suggest a part. \$\endgroup\$
    – AJN
    May 15 at 14:27
  • \$\begingroup\$ Note that many switch ratings are limited by the current they can reliably disconnect. Often they can handle a much larger current if it will never be disconnected with power switched on. Unfortunately the datasheets often don't list that specification separately. \$\endgroup\$
    – jpa
    May 16 at 7:58
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You could probably use one or more wire jumpers and Molex type headers and connectors. The exact arrangement would depend on your requirements.

Some of the 3.96mm types are rated at 10A, for example, imagine a loop of wire in the female portion: (drawing from here)

enter image description here

The female portion can easily be made in small quantities with a crimper, or any most any company that supplies harnesses and cut/crimped wires can supply them in large quantity quite inexpensively.

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