Measuring current

[slackjack]

Its there any way to measure current in a circuit without actually placing the ammeter in series with the component? Mayb there is another special device that does this?

--thank you 

 

[allvol]

Hi slackjack

An alternating current can be measured without breaking the circuit by simply placing a special loop around the current-carrying line.

With DC, however, I am not aware of any efficient, economical or accurate method.

 

[ante1]

Hi Jack,

You can use a Magnetic field sensor or a Hall Effect sensor to measure DC current. If the current passes through a resistor or a diode or just a piece of wire you can measure the voltage drop across it to calculate the current!

 

[slackjack]

Thanks for the input guys.

Ante, I'm now interested in Hall-effect (or similar) sensors. Do you by any chance havethis in your collection?

So Hall effect sensors work by detecting the magnectic field produced by moving electrons to somehow compute the current flow?

 

[SM2GXN]

That was real interesting, searched on google for "Hall-Effect Sensors measure dc current" and found this:
http://www.allegromicro.com/datafile/0704-015.pdf

 

[ante1]

Hi Jack,

Unfortunately I don’t have the book (at least not yet) in your link. But I have another one on this subject which I think is very informative, I hope you agree

 

[slackjack]

Thank you so much Ante. You're awesome. That little book is exactly the type of info I'm looking for.

 

[allvol]

Good morning, Jack

 

[ante1]

Hi Guys,

Here is a simple project showing one way to measure current using a Hall sensor. Even if you do not want to build one of these, you can learn from the circuit and description! 

Current_Clamp.rar

 

[allvol]

Very interesting, Ante.