@mrS2k... me too. I think .99 misread the channel setting. The CVR trace is at 5 v/div, not .5 v/div.

Here is a graphic.

Incidentally... a pack of 6 _fully charged_ 12 volt SLA batteries in series should read something closer to 76 or 78 volts, NOT 73. These batteries are not fully charged at all. And the sag in the voltage during the heavy 4 amp draw shows this as well.

Thanks, that makes it a lot clearer. I was almost there with eyeballing the period.

But now you've added an indicator for the zero volt line, the voltage looks overestimated to me; if one large division is 100V, it looks like the voltage is 3 / 5 of 100V, close to 60V ?


ETA: belay that. I've just realised the grid has 5 divisions per large-square-thing on the time axis, but only 4 on the voltage, so ~ 3/4 x 100 ~ 75V or so.

GAAH...

That damn LeCroy has 5 small divs horizontally and only 4 vertically per major div. So the power is EVEN HIGHER than that.

The actual Vdrop across the CVR is 1.25 volts, for a current of 5 Amps !

Therefore the actual average power is even more than 130 Watts, it is 5 x 73 x .45 = 164 Watts.



Good night Irene.

Quote from: mrsean2k on May 16, 2012, 06:31:22 PM
Thanks, that makes it a lot clearer. I was almost there with eyeballing the period.

But now you've added an indicator for the zero volt line, the voltage looks overestimated to me; if one large division is 100V, it looks like the voltage is 3 / 5 of 100V, close to 60V ?


ETA: belay that. I've just realised the grid has 5 divisions per large-square-thing on the time axis, but only 4 on the voltage, so ~ 3/4 x 100 ~ 75V or so.

Yep. damn LeCroy, fooled me too. Look what it did to the CURRENT calculation, though.