Measuring power by Clamping

[kirill007]

The clamp method isn't shit.

But it's just not as good as D'amore his tool.

We all knew(i suppose) that clamping a amp never is accurate.

You can have over 10-15% difference with measuring the same setup.

This seems to fit the idea behind d'amore tools, simple to use and very accurate and a change in the industry.

I would like to be a part of it eventually, and with that i mean buy all the equipment he has for sale.

[AMI CUSTOMS]

ok how do you measure the phase angle? and if you time v x a = watts where does the phase angle come into play. i may be making myself look like a complete moron right now but this is interesting and i want to know how it works

You would have to use a 2 channel scope with a current probe to look at the voltage and current at the same time. If you were using one of the "smart scopes" it would probably be able to tell you the difference in phase. In the example I posted above the voltage and current are about 36 degrees out of phase. Then Cosine (36 deg) = Power Factor 81%. 7,100 VA * 81% PF = 5,750 WATTS

one last question and i think im good how do you know the cosine of 36 deg = a power factor of 81 percent

Cos(36)= .81 which is 81%

Power Factor is never greater then 1.00

[AMI CUSTOMS]

very interesting! Still kind of confusing though. So the clamp method won't work even if you're not using a reactive load? It sucks that method isn't accurate...

clamp method now seems to be

No, clamp the same as before, you are still calculating apparent power at a given time, which is average power. If you know the power factor, efficiency, that is real power.

[AMI CUSTOMS]

ok how do you measure the phase angle? and if you time v x a = watts where does the phase angle come into play. i may be making myself look like a complete moron right now but this is interesting and i want to know how it works

The Power triangle is what you have to understand for AC circuits. Phase angle comes into play based on how much the current wave either leads or lags the voltage wave. In the power triangle, the bottom leg is Watts, side leg is VAR(reactive component) and hypotenuse is VA(apparent power). The angle between VA and W is your phase angle, take the cosine of that(trig lol) and you have pf(power factor).

[That1Kid]

I wanna see a vid. My brain hurts.

[zxsonnyxz]

Nice informative posts!

Studying electronics and electrical systems in "high school" really helps me understand this.

So unlike some of you, my brain got of easy this time

[Real96SS]

I'm not understanding why there is no video yet for this comparison. Car audio is all about showing results rather than talking about them. You guys can talk all day in electrical terms but it doesn't mean anything without proof and by proof I mean a video of the AD-1(because that's what were comparing clamping an amp too) with an amp on the dyno and then clamping it like everybody else does it.

[brownm3]

Nice info

One of the top 2 aviator pics. U look badass in that wife beat er' is that u? JK...

[will77530]

ok how do you measure the phase angle? and if you time v x a = watts where does the phase angle come into play. i may be making myself look like a complete moron right now but this is interesting and i want to know how it works

The Power triangle is what you have to understand for AC circuits. Phase angle comes into play based on how much the current wave either leads or lags the voltage wave. In the power triangle, the bottom leg is Watts, side leg is VAR(reactive component) and hypotenuse is VA(apparent power). The angle between VA and W is your phase angle, take the cosine of that(trig lol) and you have pf(power factor).

dude i never took trig in my life but this makes perfect sense thanks for taking the time to explain it

[snafu]

Tony D' has the uncanny ability to explain some of the most complex topics in terms that anyone can grasp. Guys - sometimes it's not all about a demo - we all know one plus one is two. Do we really need two apples on the desk in front of us to believe it? BECAUSE some of this stuff requires a complete understanding, many companies over the years have taken great liberties in their performance claims. After all, if we don't know the facts, how could we challenge them?

Always, remember the following:

-If it seems too good to be true, it probably is

-The laws of physics are not just really good ideas, they are LAWS

Study your math! Now, back to your regularly scheduled programming with Dr. D'. I'm tuned in too - I can't tell you how many things he's taught me over the years.