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    Electronic Load Circuit for 380 Vdc (2A to 3A) Power Supply

    Hello again all...I got a 380Vdc (2 to 3A) power supply here, i am on the way of building a load test station. First i thought of using a series of high power resistors. But have heard that electronic load is more better. Do you have guys a link or schematic diagram for simple electronic load can handle 380Vdc ? thanks in advance!

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    Re: Electronic Load Circuit for 380 Vdc (2A to 3A) Power Supply

    1200W, at 400V, beware the extra breakdown effect for mosfets above 60V, I expect you will need to use 250W fets, at 30W each, giving 40 mosfets min to avoid 3rd break down ... We got our last DC load box here: http://www.pwrtrnx.com/index.cfm/4,457,html modified to 450VDC at 8A.



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    Re: Electronic Load Circuit for 380 Vdc (2A to 3A) Power Supply

    Hi,

    But have heard that electronic load is more better.
    In which regard?
    Cost --> no
    Ruggedness --> no
    Size --> no
    Power dissipation --> no

    Klaus
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    Re: Electronic Load Circuit for 380 Vdc (2A to 3A) Power Supply

    [QUOTE= modified to 450VDC at 8A. [/QUOTE]


    Thanks, possible to share the schematic diagram? Or are you selling this unit?



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    Re: Electronic Load Circuit for 380 Vdc (2A to 3A) Power Supply

    I'm just saying that due to extra "third breakdown" effect of fets run in linear fashion at high voltage ( they must be seriously de-rated ) - rather than the hassle of going through this learning curve & trying to build our own, we found the above load box and ordered one - no tears, no delay - and if it fails we send it back for repair / replacement ... had ours 5 years now.



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    Re: Electronic Load Circuit for 380 Vdc (2A to 3A) Power Supply

    The only reason electronic loads are better vs power resistors, is that it is continuously adjustable (or in very tiny increments) and its transfer function can be changed from resistive to constant current, constant power or constant voltage.

    Having said that, a 1200 watt e-load is not a trivial design. Not for a beginner. My first e-load was only 50 watts, and took a while to correctly design the closed loop response, otherwise it will fight against the UUT's own control loop.

    If you are ONLY planning to test a single or very few supplies, nothing beats the cost and simplicity of a bank of power resistors. With simple switches you can make it adjustable (in coarse steps).
    Otherwise, it is best if you purchase or lease a commercial e-load as Easy Peasy has suggested.
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    Re: Electronic Load Circuit for 380 Vdc (2A to 3A) Power Supply

    OK so for this case, I will use resistors. I got here 20-ohm/25W (18qty) + 10-ohm/20W (2qty). Total 380-ohms. I want to test with 1A load set-up...Thanks to all.



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