BsudRC
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Yes I got 5 from Amazon, I have put one on each of the 2 packs. These battery packs are brand new. Both the alarms did same thing on both batteries.
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You need to see what the IRs and the voltages are on each the lipo cells. Also what lipos are you using? What rig are you using these LiPos in?
BsudRC
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These are 4s hovoos I checked the cell voltage right out of the boxes and both packs all 4 cells were reading right around the 3.8v so I'm pretty sure the Packs are fine. I'm running these packs in a Arrma 4s mojave
Grizz03
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Have you charged these batteries or trying them at the 3.8v storage level them came at?
Testing a LVC you set at 3.6v with batteries at 3.8v it will do what you're experiencing with the alarm going off.
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BsudRC
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No I've charged them full and ran them in my truck but as soon as I start running my little alarm things start Alarming. I set them at 3.6v but the packs are fresh around 4.2v so I just can't understand if the Alarms is set at 3.6v why the heck they start Alarming as soon as I start running. When they do that I just unplug them and Run my Truck for 15 mins and plug back in to see what my voltage is, and it's usually down to around 3.8v per cell after 15min of running.
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Do you not have an IR meter on your charger? Curious what the IR's of your batteries are showing. Hoovoo's are not good batteries, so I suspect you are getting a huge voltage drop under load. That is about all it can be unless your battery alarms are all junk.
BsudRC
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I just got a gensacearespammers imars d300 g tech. Not sure if it test IRs or not I'm still learning it
you're charger reads IRs. I've circled in red what you're looking for. You can only see it after a full charge.
I would also try a couple of the other alarms that you have just to make sure.
BsudRC
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Ok so what should they be?
Does this charger check irs?
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Go through the menu and see if you find IR reader or Internal Resistance setting. If not then no it doesn't have it.
Just checked, doesn’t have it. How would I check with a multi meter?
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Idk
Okay.
https://www.rctalk.com/forum/threads/lipo-internal-resistance.136608/#post-1359284
You can't check battery IR's with a regular multimeter. When measuring IR's for batteries and capacitors, you have to measure the voltage drop across a load and then do some minor calculations. This is not the best way to measure IR's, but it will get you in the ballpark. See below for a blurb I pulled off the internet.
"To measure the internal resistance of a battery, you would typically:
- Measure the Open-Circuit Voltage (OCV): This is the voltage of the battery when it's not under any load (i.e., when no current is flowing).
- Apply a Load: Allow a known current to flow through the battery by connecting it to a load, and then measure the voltage under load.
- Calculate the Voltage Drop: Subtract the voltage under load from the OCV to find the voltage drop due to the internal resistance.
- Calculate the Internal Resistance: Use Ohm's Law to calculate the resistance. Rearranged to solve for resistance, the formula is:
R=VIR=IV
Where VV is the voltage drop and II is the current through the battery.
- Measure the OCV of the battery, let's say it's 12.6 volts.
- Apply a load that draws a known current, say 2 Amps, and measure the voltage under load, which might be 12.4 volts.
- Calculate the voltage drop: 12.6V−12.4V=0.2V12.6V−12.4V=0.2V.
- Calculate the internal resistance: R=0.2V2A=0.1ΩR=2A0.2V=0.1Ω.
If in the ballpark is all you're concerned about, then you can either buy a charger that has that ability built in (preferable) or you can opt for something cheap like THIS, but you'll have to measure one cell at a time. BE CAREFUL THOUGH! If you accidentally touch your probe leads together while they are in contact with the balance leads, and you'll likely ruin that cell by short-circuiting it!
DISCLAIMER!
I've never owned or operated that supposed cheap IR tester, but it should work. It uses four wire test probes, so it should be capable.
https://www.amazon.com/ALLOSUN-Batt...rnal+resistance+reader+battery,aps,156&sr=8-1
