Power output point

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This is a very simple project, but maybe other people can use the idea.

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On my main workbench I have lot of bench meters, electronic loads and other stuff, this gives me a bit of an issue with my power supplies, because I want very short wires from them (or remote sense).

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With the Keithley precision power supply I made the above box when I got the supply, mostly because it only had remote sense on the back.

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But for my big supply, that is way to big to be close to my working space, it is about one meter from my work area. I had some binding binding posts at the end of a thick cable, but without remote sense. That is two problems: one is the lacking remote sense, the other is that binding posts cannot handle the full current of the supply.

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First I made some cable with connection that could handle full current, the cable is 25mm2. I do not have any tool to crimp that with and instead I soldered it (That is not the ideal way).

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I wanted input and remote sense for connection to the power supply and for the output both regular binding post and some high current types.

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For the high current binding post I found some on ebay, they are rated for 100A or 200A (The low value in specifications, the high in headings).

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For the regular binding posts I uses the models I always uses, the large model is rated 30A the small model 20A and the treads are in metal.

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The small is for sense, the large is for output.

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I wanted some very solid connections between the different connectors and the sense got a separate connection from the output binding posts.

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Ready to use with high current input and sense feedback.


Measurements

There is not much to measure, but I adjusted the current on my supply to maximum and low output voltage, then I shorted the output binding post with a short thick copper wire:
Even though the remove sense is connected to the bottom of the binding post I still looses 10mV across it and the connection to the shorting copper wire (that is 0.2mOhm).
The 0.071V at the input means I looses about 2.5 Watt in the box.

A voltage test: Remote sense works very nicely, the voltage at this output box is stable.



Conclusion

With this box I do not need a voltmeter to check input voltage or do any load depend voltage compensation on the power supply, the voltage I set on the power supply is the voltage I have at my working point. If I need to compensate a few extra connections I can easily move my remote sense point now.
The other advantage is that I can use all 50A for testing.


Notes

The two power supplies are:
The small one: Keithley 2280S-32-6: 32V 6A with precision voltage and current meters
The large one: TTi QPX1200SP: 1200W 60V 50A (U*I is limited to 1200W).