While on the subject, any one familiar with the Kill A Watt meter? This listing sells for US$26 and free shipping:
https://www.amazon.com/P3-International-P4460-Electricity-Monitor/dp/B000RGF29Q I swapped out the 2 mOhm current sensing resistor with a 0.2 ohm resistor (and of course greatly limiting the current capability) so I can measure standby power down to 10 mW. I did test with a 7 W incandescent light bulb and it reported reasonable readings. I tested are few phone chargers with nothing plugged and they idle at less than 50 mW. (But I don't know if I trust the figure down to decimal point:) It could be a really inexpensive way to get a reasonable (but not certification grade) power measurements. Best Regards, Alfred On February 12, 2018 1:36:10 PM PST, Brian O'Connell <oconne...@tamuracorp.com> wrote: >Will admit to having done this stuff with using microcontrollers and >discrete sequential data channels and of sufficient sampling speed, but >am subject to frequent bouts of idiocy. And this was for process >control, and thus not a Type Test. Also, note that there is a >difference in technique and equipment between power loggers and an >analytical instrument. > >Best done with an instrument intended for this measurement; that is >'power analyzers'. Typically found on shelves at Keysite, Tektronix >(nee Voltech), Ametek, Chroma, etc. And many Tek and keysite DSOs have >a 'plug-in' for doing power measurements. All of this instrument-grade >stuff can easily handle external sensors. > > >Brian > >-----Original Message----- >From: Amund Westin [mailto:am...@westin-emission.no] >Sent: Monday, February 12, 2018 1:05 PM >To: EMC-PSTC@LISTSERV.IEEE.ORG >Subject: [PSES] Current measurement > >If you want to calculate the consumed power (W) in a 1-phase AC >circuit, you >can use a current clamp-on device to measure the current in one >lead/wire >and multiply with the applied voltage. >But with such a current clamp on device, to we measure the apparent >power >(VA) or the real power (W)? > >Best regards >Amund > >- >---------------------------------------------------------------- >This message is from the IEEE Product Safety Engineering Society >emc-pstc discussion list. To post a message to the list, send your >e-mail to <emc-p...@ieee.org> > >All emc-pstc postings are archived and searchable on the web at: >http://www.ieee-pses.org/emc-pstc.html > >Attachments are not permitted but the IEEE PSES Online Communities site >at http://product-compliance.oc.ieee.org/ can be used for graphics (in >well-used formats), large files, etc. > >Website: http://www.ieee-pses.org/ >Instructions: http://www.ieee-pses.org/list.html (including how to >unsubscribe) >List rules: http://www.ieee-pses.org/listrules.html > >For help, send mail to the list administrators: >Scott Douglas <sdoug...@ieee.org> >Mike Cantwell <mcantw...@ieee.org> > >For policy questions, send mail to: >Jim Bacher: <j.bac...@ieee.org> >David Heald: <dhe...@gmail.com> -- Sent from my Android phone with K-9 Mail. Please excuse my brevity. - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
