I'm having trouble understanding the part related to power and its calculations, sorry for my ignorance.

I have a three-Phase 380Vac System with no Neutral wire available and i need to power the following SMPS from the available 3 wires:

"Input voltage 100~120Vac (0.6A) or 200~240Vac (0.35A) 50/60Hz and dual output +12Vdc/2A & +5Vdc/6A"

Is it possible to use the following schematics to power it up ?

enter image description here

Transformer Ratings (As per information's included on the back, nothing else): Primary: 380Vac (line to line) 50Hz Secondary: 110Vac 50Hz @ ~ 0.7 amps.

And if there is another way to achieve the same output ratings as SMPS, Please Enlighten me.

  • \$\begingroup\$ Should be fine. Is your SMPS Class I or II? \$\endgroup\$ – winny May 12 '18 at 19:36
  • \$\begingroup\$ Actually i couldn't tell there nothing on the website more than what i mentioned earlier, link , it's Industrial Chinese SMPS, \$\endgroup\$ – Amr Sohil May 12 '18 at 23:35
  • \$\begingroup\$ What is the difference?, ans will powering it from the transformer affect the Dc current output ? As i understand, These SMPS's increase the frequency to increase the power, from 50hz upto 70khz is that correct? \$\endgroup\$ – Amr Sohil May 12 '18 at 23:40
  • \$\begingroup\$ Your system will work.Your 50Hz transforwer will be much bigger than the SMPS .You could use a transformer with say a 24VAC secondary and just buck this down .This will be much more reliable than the chinese SMPS and more efficient . \$\endgroup\$ – Autistic May 13 '18 at 4:22
  • \$\begingroup\$ Do you mean bigger than SMPS in current ratings ? and also i have no problem using 24ac directly from transformer but my connect equipment will require almost 5vdc @ ~5A. if i used transformer 380-24 @ ~0.7A , will be capable of providing the required DC Current ? sorry if i look stupid :D \$\endgroup\$ – Amr Sohil May 13 '18 at 13:46

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