Right now I am planning an electrical conduits and wall socket that is going to be used with a welding inverter, and encountered the following problem:

  1. Let's assume inverter maximum consumption is 5 kVA, which is 21.7A at best (assuming cos(phi)==1) at 230V (which we have here in Russia).
  2. Inverters of such power uses a standard Schuko plug.
  3. Wall socket for this is designed for 16A maximum.

These three points taken together sounds like a contradiction for me. Here is my thoughts on that: ok, let's assume a quality wall socket is more or less safe to use at 20-25A (actually I am not sure on how valid this assumption is, please let me know). Then, if I use 4 mm^2 copper wires, that should solve my problem. But, it seems that wall sockets designed for 16A current takes only 2.5mm^2 wires :(

Also I cannot cut a manufacturer's plug off inverter and use something designed for 32A, as this voids my warranty.

  • Welders are weird -- they consume power in pulses, for one, which means normal current draw calcs don't hold for 'em. So, what's the rated duty cycle of your welder, or what is its nameplate effective current for that matter? – ThreePhaseEel Oct 8 '17 at 18:26
  • @ThreePhaseEel I have no information about the duty cycle, all I have for one particular device is: current consumption 23A (no details), power consumption 5 kVA, energy conversion efficiency: 85%. I can post full characteristics available if that helps. – Alexey Malev Oct 8 '17 at 18:33

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.