Clamp Meter

[BaseSteala112 10+ year member]

So the formula would be P=I*E and R=E/I?

V=IR

P=IV

 

[JimJ 5,000+ posts]

So what's the difference between using a clamp meter or getting your amp bench tested?

"Bench testing", at least how I use the term, means you're using a stable power supply that won't drop like an overtaxed charging system might, and you're driving the amplifier into a purely resistive load, not a speaker that has both inductive and resistive components that depend on frequency.

 

[danteBirosel 5,000+ posts]

V=IR
P=IV

lol that's exactly wat i said. In Ohms law the V is E. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[BaseSteala112 10+ year member]

"Bench testing", at least how I use the term, means you're using a stable power supply that won't drop like an overtaxed charging system might, and you're driving the amplifier into a purely resistive load, not a speaker that has both inductive and resistive components that depend on frequency.

Gotcha //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[BaseSteala112 10+ year member]

lol that's exactly wat i said. In Ohms law the V is E. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

lol, i know that. I was just confirming what you said was right.

 

[TeamPSI 10+ year member]

And for the normal guys...

If you want to see what kind of power your amp is producing you will be best off to use a single note. This is normally done by "us" spl guys to check output power during our spl burps. This is ONLY giving you power and impedance at this one frequency. Changing enclosures and subwoofers will always change your results. You will also see varying impedance results when different amounts of power are applied to the subwoofer.

You will measure AC amperes and AC voltage. Multiply these together to get output power. Ex - 50 volts and 25 amps = 1250 watts

To obtain the actual impedance at this frequency you will divide voltage by amperage. Ex - 50 volts divided by 25 amps = 2 ohms

Get it?

 

[danteBirosel 5,000+ posts]

got it. thanks for explaining it....

 

[BassAddictJ 5,000+ posts]

Expect to spend $70-$150 on a good meter...

ya...i bought one of those $20 one off ebay...not only that one was a POS, but i emailed the seller and he agreed to send another one.......ALSO a POS .....

spend the extra money, geta solid one

 

[BassAddictJ 5,000+ posts]

My Harbor Freight clamp is just as good as anything else I've ever used.
I also have a Clarke-Hess RMS power meter that I have compared it to and it gives the same exact results. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Twenny Dolla http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=42397

AAAAAAAAAAAHHHHHHHHHHHHH thats the one i got off ebay.........weird, mine sucked....... i mean i know at full tilt one of my 1501d's does more than 4 amps....... i know my electrical system is NOT that shitty to where it wangs full tilt very very hard yet i get only 4 or 5 amps on the clamp meter.......

 

[qtipextra 5,000+ posts]

Theres another use for a clamp meter, and thats to measure DC amperage. You can see much actual current you are drawing from the alt.

I dont see many clamp meters that measure DC current tho.

 

[DBfan187 5,000+ posts]

Theres another use for a clamp meter, and thats to measure DC amperage. You can see much actual current you are drawing from the alt.
I dont see many clamp meters that measure DC current tho.

WTF do you think it's used for in car audio then?
//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

 

[qtipextra 5,000+ posts]

WTF do you think it's used for in car audio then?
//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

Somebody asked what the uses of a clamp meter are. There is the use of more closley calculating your output power from your amp. There is ALSO the use of measuring DC current, like I stated above. I was simply imforming the other uses of a clamp meter. And measuring DC current in your car can be helpful. My rebuilt alt was acting up. I pulled out a clamp meter, and measured total amperage draw, which was about 80 amps at full volume. The alt was supposed to be able to put out 130 Amps. And at full volume, I had voltage drops down to 12.5v.

Either way, it has to do with car audio.