Author Topic: AC Voltage Component of DC with Analogue & DMM  (Read 2260 times)

0 Members and 1 Guest are viewing this topic.

Offline zenoidTopic starter

  • Newbie
  • Posts: 6
AC Voltage Component of DC with Analogue & DMM
« on: February 21, 2014, 07:11:41 pm »
hi all - i use an Avo 8 mk6 meter for my model railway hobby & other. - i don't have a DMM.

a few days ago my led tv packed in.
i thought it was the psu caps however they looked ok so i decided to check the single 12vdc output. that too was ok but when i switched the avo to ac a reading of about 25vac was displayed.

i was rather confused by this & posted on another forum regarding. there i was informed that the  ac component of a dc source could not be measured correctly using an analogue meter.

however regarding a DMM, conflicting advice was given  - some said the ac component could be tested others, not.

i would therefore be grateful if someone could enlighten me before i buy one.
 

Offline HKJ

  • Super Contributor
  • ***
  • Posts: 2904
  • Country: dk
    • Tests
Re: AC Voltage Component of DC with Analogue & DMM
« Reply #1 on: February 21, 2014, 07:43:45 pm »
This depends on the meter, some meters has a capacitor blocking DC when measuring AC.
If a meter has both AC and AC+DC setting, then the AC settings has a capacitor blocking the DC.
 

Offline zenoidTopic starter

  • Newbie
  • Posts: 6
Re: AC Voltage Component of DC with Analogue & DMM
« Reply #2 on: February 21, 2014, 08:03:19 pm »
This depends on the meter, some meters has a capacitor blocking DC when measuring AC.
If a meter has both AC and AC+DC setting, then the AC settings has a capacitor blocking the DC.
hi HKJ - many thanks for that -  by any chance you wouldn't have a make/model that would have that function?


 

Offline HKJ

  • Super Contributor
  • ***
  • Posts: 2904
  • Country: dk
    • Tests
Re: AC Voltage Component of DC with Analogue & DMM
« Reply #3 on: February 21, 2014, 08:12:14 pm »
hi HKJ - many thanks for that -  by any chance you wouldn't have a make/model that would have that function?

Yes: Fluke 189, Fluke 289, Agilent U1272A, Gossen MetraHit energy

That is because they are high end DMM's, you can also find many cheaper DMM's with that function.
 

Offline zenoidTopic starter

  • Newbie
  • Posts: 6
Re: AC Voltage Component of DC with Analogue & DMM
« Reply #4 on: February 21, 2014, 10:57:52 pm »
Yes: Fluke 189, Fluke 289, Agilent U1272A, Gossen MetraHit energy

That is because they are high end DMM's, you can also find many cheaper DMM's with that function.

thanks again.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf