1. Why is "no load power input 75mW max @230V AC 50-60Hz", but input is "100-240V ~ 50-60V 0.5A which results in 115W (230V x 0.5A)?

  2. What do the 3 symbols mean?

Thank you for reading and answering. Just want an understanding. It is a vacuum cleaner charger.

  • \$\begingroup\$ @brhans how did u insert the photo into the post and do u know the answer? Thank you. \$\endgroup\$ Mar 27 '21 at 5:04

The no-load power input is the power the supply itself consumes when is not delivering power to a load.

The supply DC output rating is 22 V 0.75 A, or 16.5 Watts. The 100 - 240V 0.5A rating is probably a minimum rating required by some electrical codes. The supply should not draw anything near that if it only delivers 16.5 Watts.

  • \$\begingroup\$ Would the 0.5A be the peak current at a short before any internal short circuit protection kicks in? \$\endgroup\$
    – Passerby
    Mar 27 '21 at 5:15
  • \$\begingroup\$ Why wouldn't it draw anything near that if it only delivers 16.5w? \$\endgroup\$ Mar 28 '21 at 6:23
  • \$\begingroup\$ @Alienxalienz: 16.5 Watts would only be 0.165 Amp at 100 volts. If the supply efficiency is only 50 %, it would only draw 0.33 Amp. \$\endgroup\$ Mar 28 '21 at 16:04

The top symbol indicates a switched mode powersupply.

PS05 appears to be a Kärcher designation for a power supply producing 22VDC at 0.75A with that DC connector. Searching Kärcher PS05 found me images of USA and Europlug variants.

The bottom symbol looks like a drawing of the DC end showing polarity.

16.5W but 0.5A, at 0.5A there's no regulation of power factor, it really could be that bad, or the 0.5A claim could be strategic, giving the manufacturer the option of substituting a supply circuit with a worse power factor (up-to 0.5A) in the future.

  • \$\begingroup\$ The 0.5 A has very little to do with reality. When you go for CE, UL or similar certification, the certified body tests that you are below the rating. For all products I’ve designed and put forward for approval, it’s maximum continuous power consumption divided by minimum input voltage, plus margin and round up that number and you get a pass. \$\endgroup\$
    – winny
    Mar 27 '21 at 8:12
  • \$\begingroup\$ Thank you but i dont understand what u meant in the last paragraph( 16.5w but ..... power factor regulation???) \$\endgroup\$ Mar 28 '21 at 6:22
  • \$\begingroup\$ by regulation, I meant laws and other legal requirements. \$\endgroup\$
    – Jasen
    Mar 30 '21 at 10:31

Your Answer

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

Not the answer you're looking for? Browse other questions tagged or ask your own question.