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Voltmeter at tech station.

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Voltmeter at tech station.

Old 10-13-2023, 02:07 PM
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It's not only about safety. Today most high quality cells will be produced as HV (whether it says on the outside or not), so anything below 4.35V per cell should be safe with these. The strict limit of 4.20V is to ensure a level playing field (mostly for stock classes - we rarely tech mod classes for voltage), since more voltage usually also equals more punch.
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Old 10-13-2023, 03:57 PM
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Originally Posted by mrreet2001
irrelevant to my question.
Your question was what precision meters are others using. It's very relevant.
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Old 10-14-2023, 08:42 AM
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There has to be a tolerance or grace range. And while we've generally been getting by with whatever nonsense voltage the RD chooses.......

4.3 would be the best cutoff voltage for DQ at all the tracks I've seen. Hundredths, should be ignored as insignificant.

4.2 and 4.27 are the same based on the tolerances of the meter. Do we see repeatable results down to hundredths? Sure. But it's sloppy.

I just dial in my charger to a few hairs over the RD's cutoff, then use his meter and infrared to check my battery before practice. (Keep in mind that your battery will cool, away from the charger)
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Old 10-14-2023, 02:43 PM
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Originally Posted by gigaplex
Your question was what precision meters are others using. It's very relevant.
I ask what meters are used at the tech station. Not seeing the relevance of how accurate random chargers are. Thatís the point of using accurate and consistent tools at the tech stations.
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Old 10-14-2023, 02:48 PM
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Originally Posted by gotheframe
Lucky for you I was the one asking a question.

Do share though how you intend to control charging to the thousandth.
Tracks donít control what chargers people use only the max voltage allowed. Someone could show up with a charger that doesnít even have displayed voltage. Wonít matter as long as itís charging below the max allowed. 🤷‍♂️

.. but since you must know, Ichargers read out that far.
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Last edited by mrreet2001; 10-14-2023 at 03:00 PM.
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Old 10-15-2023, 02:25 AM
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There is no over allowed voltage limit. If its over its out. the thousandths is absurd, My Fluke 123 scopemeter will measure that value . im not packing a 2000$ to the track
all this trying to get around the rules is a joke. thanks for the lol
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Old 10-15-2023, 03:21 AM
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And I have to recalibrate my Icharger to the tracks meter every damn big race. And hope he doesn't clean his leads.

I'm startled that we've gotten by this long, using hundreds of a volt as a significant digit. It is possible to follow the 4.23 rule is too high, get down to 4.20 to race rule, but it's absurd.

Guy with the cleanest charge leads, wins. Lol. It's just another anal retentive nuisance of stock class racing.

Last edited by Zerodefect; 10-15-2023 at 03:49 AM.
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Old 10-15-2023, 03:40 AM
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Originally Posted by Zerodefect
And I have to recalibrate my Icharger to the tracks meter every damn big race. And hope he doesn't clean his leads.

I'm startled that we've gotten by this long, using hundreds of a volt as a significant digit.

Guy with the cleanest charge leads, wins. Lol. It's just another anal retentive nuisance of stock class racing.
0.01 of a volt won't make you win. Batteries often fluctuate that much walking over to tech.
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Old 10-15-2023, 03:40 AM
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We don't usually DQ people, but we will not let them start with over voltage either, even with as little as 4.21V per cell (people usually don't show up with more than 8.42V). 4.3V however is way over, though. Closer to HV voltage than regular - we'd probably DQ that, since that is way too much to happen by accident IMO. But we allow people who are only slightly over to just pull the trigger on their radio for 20 seconds or so, until they measure at or below the limit.
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Old 10-15-2023, 03:47 AM
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Originally Posted by gigaplex
0.01 of a volt won't make you win. Batteries often fluctuate that much walking over to tech.
I'm seeing 0.05 fluctuation. Which is the problem. It's only dumb luck that this hasn't been an issue for anyone yet.

I havent really noticed much difference in performance, within reasonable voltages and IR's. My fastest pack, often doesnt have numbers supporting that its actually the fastest. Even after 3 cycles.

My 4s Protech shreds my 4s Reedy, for example. But the charger can't tell me why.
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Old 10-15-2023, 03:57 AM
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Originally Posted by Zerodefect
I'm seeing 0.05 fluctuation. Which is the problem. It's only dumb luck that this hasn't been an issue for anyone yet.

I havent really noticed much difference in performance, within reasonable voltages and IR's. My fastest pack, often doesnt have numbers supporting that its actually the fastest. Even after 3 cycles.

My 4s Protech shreds my 4s Reedy, for example. But the charger can't tell me why.
Well then you've just answered your own question on why we don't use 3 decimal places.
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Old 10-15-2023, 04:22 AM
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My meter gets fluctuation of 0.02-0.03v just sitting.

If I do get it to scale 0.000, it'll bump me up to 0.00 or fault on OR, as soon as it sees an Rc battery.

Even the meter knows this is silly. No big deal, but I think we're just wasting peoples time when a car tech's 0.03 high.

Last edited by Zerodefect; 10-15-2023 at 04:58 AM.
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Old 10-15-2023, 11:38 AM
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Originally Posted by Zerodefect
My meter gets fluctuation of 0.02-0.03v just sitting.
Your meter sucks.
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Old 10-15-2023, 11:40 AM
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Originally Posted by the rc guy
There is no over allowed voltage limit. If its over its out. the thousandths is absurd, My Fluke 123 scopemeter will measure that value . im not packing a 2000$ to the track
all this trying to get around the rules is a joke. thanks for the lol
So jealous

But I would bring it to the track, just to be a dick
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Old 10-15-2023, 05:20 PM
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Originally Posted by jiml
Your meter sucks.
Nothing wrong with my meter.

It's saved my life, literally, about 11 times.
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