New Battery Help Needed

[jondilly1974]

Just got my new Orvonics 3S 7600mah 50C battery this week and went to use it today for the first time in my BLX120 equipped 3S Typhon and it went fast for the length of a parking lot (200’) and then went LVC on the return to me.

Before I left to head to the lot, I balance charged the new battery with my Tenergy TB6-B charger until it finished. Headed out to the parking lot down the street. Fired it up and got one single pass before LVC. I turned it off and back on and got another half of a pass and LVC again. It goes really hard, aka wheelies well, for that few seconds and then LVC again. ESC fast blinking.

I return home dejected and the pack is sitting at 11.83VDC (3.94VDC per cell). I just put it back on a balance charge again to see if it happens again.

Any advice or input here? I’m gonna change up one of my PowerHobby 5400mah 3S 50C packs as well to see if that pack also LVCs that fast.

More rig info:
Started as a Granite 3S BLX
Converted to Typhon 3S
Upgraded to BLX120 & 2400kv from 4S Arrma
Running 18T pinion
ProLine RoadRage 3.8 wheels
Dry flat parking lot

Gonna take my GoPro next session to take video in case it happens again.

 

[PaPa Thorn]

But nothing happens when you use another battery, or haven't you tried? Can you try it in another vehicle?
If you're sure it's the battery I'd contact the seller. Sounds like you got a dud.

 

[jondilly1974]

But nothing happens when you use another battery, or haven't you tried? Can you try it in another vehicle?
If you're sure it's the battery I'd contact the seller. Sounds like you got a dud.

All my other packs are at storage, but I can toss one in and see quickly. My street isn’t as easy to open it up. Parked cars and speed bumps keep my trigger finger at bay.

 

[arrmadillo]

Try another battery in it, then take it from there. If you have another rig you can try the 1st battery in it.

 

[jondilly1974]

Try another battery in it, then take it from there. If you have another rig you can try the 1st battery in it.

My other rig, a Granite 4x4 Mega is down at the moment. Stole too many parts keeping the BLX running ??
So I let it charge fully

Charge verified by DVM...

Took it back to the lot and it ran four lengths of the lot before LVC, which was probably under a minute of runtime. Uploading some video and will post it here when it finishes.

 

[arrmadillo]

Very strange. Could be esc?

 

[jondilly1974]

Very strange. Could be esc?

I’m charging one of my PowerHobby 3S 5200mah 50C batteries and am gonna try that one out.

 

[jondilly1974]

Ok similar results on the PowerHobby 3S 5200mah 50C battery. It runs hard for about a minute and then goes LVC. This time I kept running it full throttle in LVC just for S&G. Good thing I was in a wide open area in a straight line because the power kicked back on and did a backflip. Turned it over and had another 20ft of full power and then LVC again. ESC LED blinking again. Power off and then on, no blink. Full power again for 2 seconds, then LVC again.

So I don’t think it’s batteries per se. I don’t have another BLX120 to swap in. I do have a BLX100 that I can swap back in. Is it OK to run the BLX100 with the 2400kv motor?

I am beginning to think this is a charger issue. I may run to the LHS in the morning to buy a new charger. ??‍

 

[jondilly1974]

Here is the video with the Ovonic battery

 

[Lazy Bushman]

Do you have any of those little tester/alarm jiggers that you connect to your balance lead and give you a per cell reading like your charger can? Would be interesting to see a comparison post charge then post LVC

 

[arrmadillo]

See if someone will lend you a charger or hobby shop will charge them for you. What if it's not the charger, if not you will be stuck with a new charger you didn't need.

it's the same with an electrical problem with a car. Try to diagnose the problem the best way you can without replacing unneeded parts. It's expensive and your stuck with parts you can't return. I would try to switch out esc's.

 

[jondilly1974]

See if someone will lend you a charger or hobby shop will charge them for you. What if it's not the charger, if not you will be stuck with a new charger you didn't need.

it's the same with an electrical problem with a car. Try to diagnose the problem the best way you can without replacing unneeded parts. It's expensive and your stuck with parts you can't return. I would try to switch out esc's.

I really want a new charger anyways, so that’s not a big deal to me. I bought one last night on Banggood. It was the SKYRC B6 Nano Duo. Bad thing is it won’t be here for weeks.

After sleeping on the problem, I have a few things to try.

1) I recently bought a JST-XH extension cable to extend the balance connection. I’m going to try to charge without that extension cable.

2) I recently became aware that I should balance charge every time. I didn’t used to do that. I used to just use the Lipo Charge setting, instead of Lipo Balance. I am going to try this second if the extension cable isn’t to blame.

3) Swap back to my BLX100 ESC

4) I will take a battery to the LHS and ask them to charge it for me.

 

[Notorious J]

Hi @jondilly1974. A volt meter is going to give you excellent readings, so I honestly don't think it's your charger or batteries. Does the fan on the blx120 work? With a fully charged battery, shutting down that quick sounds like it's either thermal shutdown, or the esc is pooched. I don't have a 3s Arrma, but I would start by removing the motor from the truck, and running it freely to see how long it goes before cutting out. If it's still really short, then it's likely the esc is just no good. My gut says the problem is heat, not voltage. If it runs longer while outside the truck, try a smaller pinion and check that nothing else is binding in the drivetrain. Trial and error is a pain, but worth doing the work before buying new parts.

 

[jondilly1974]

Hi @jondilly1974. A volt meter is going to give you excellent readings, so I honestly don't think it's your charger or batteries. Does the fan on the blx120 work? With a fully charged battery, shutting down that quick sounds like it's either thermal shutdown, or the esc is pooched. I don't have a 3s Arrma, but I would start by removing the motor from the truck, and running it freely to see how long it goes before cutting out. If it's still really short, then it's likely the esc is just no good. My gut says the problem is heat, not voltage. If it runs longer while outside the truck, try a smaller pinion and check that nothing else is binding in the drivetrain. Trial and error is a pain, but worth doing the work before buying new parts.

All good advice. I appreciate the great info. The motor and ESC are new, as well as the 18T pinion, but my feeling is they seem like new. Fan on the ESC and motor both working fine. Temps are very low. I have a video I shot last night that is still processing to YT that shows that. If it ever finishes I will post it here. As far as a smaller pinion, I would have thought that too if I were running on grassy hills, but it was a dry flat parking lot, so I’m not really sure that applies? Please correct me if I’m wrong.

And another bit of info here, I recently RMAd one of my PowerHobby 3S 5200mah 50C packs due to very short runtime. This was before the BLX120 swap. This was on stock 15T pinion too. I’m really thinking there’s an issue charging somewhere.

How can I test individual cells? My charger doesn’t seem to have the function. Is it as easy as testing the individual pins on the balance connector with my DMM? One pin is common and the other 3 are POS for each cell? Wondering if I had a bad balance cable or board, could one cell/circuit be bad causing severe voltage sag on one cell, sending the ESC into LVC?

I have one of the PowerHobby 3S 5200mah 50C packs on the charger without the JST extension cable to rule that out.

I can also quickly run my old BLX100 & 3200kv setup with any of the packs out of a truck too. Would that help narrow this down? I can grab my Mega radio set and use the BLX100 setup to test for quick drain. ??‍

 

[jondilly1974]

Here is a link to me testing for heat with my finger, which is certified and calibrated to a very tight tolerance

 

[jondilly1974]

And here is the run just before I checked for thermal above. Sorry this is out of order but YT was being funky with my upload.

 

[jondilly1974]

Ok, so I charged two packs (Ovonics 7600 & PH 5200) using the “Lipo Charge” setting instead of the “Lipo Balance” setting on my Tenergy TB6B and had quite a bit more runtime before it slowed down. I again was running the RoadRage 3.8s, first with the PH 5200. After about 5 mins, it did the LVC slow mode deal. Power cycled and it ran for another two mins to LVC. Power cycled and then ran for 30 seconds to LVC. At that point the motor stopped turning, steering and fans operating normally. Pack was down to 11.49VDC with the fans still running. Back of motor can was hot to the touch this time. Couldn’t keep my finger on it more than a few seconds.

Decided to try out the Ovonics 7600 with my RoadRage 2.8s instead of the new 3.8s. Obviously it ran a lot slower on the top end, but it ran for about 10mins until LVC, which was a huge improvement over last nights 1min runs.

So two factors here:

1) Tenergy charger doesn’t seem to fully charge on balance setting

2) RR 3.8s on an 18T pinion may be too much for this motor/ESC combo?

Charging the Ovonics 7600 up again to run it on my Badlands 2.8s to see how that holds up.

 

[Notorious J]

@jondilly1974, a good charger should be able to show you individual cel stats, but for just a few bucks, you can buy a voltage checker that you plug your balance plug into.
https://www.amazon.com/Readytosky-Battery-Voltage-Precision-Indicator/dp/B073558SN6
This is just one example. You definitely don't want to get in the habit of not balance charging. Your going to shorten the life span unnecessarily. I would also try a total restart on the esc, and carefully check the settings. Your lvc might be set too high, so restoring it to factory defaults would be one other place to start. Hopefully you get this all sorted out, and enjoy the long run times those batteries have to offer.

 

[Captain Dirt]

That charger you have will show you individual cell stats. Just push the right arrow while it's charging and it'll show you all the cells and their voltages. Just gotta play around with the buttons while you're charging to see what it's capable of. The only downside of the TB6B is it's only rated at 50w for charging. Your 7600mAh lipo must take a long time to charge.

 

[jondilly1974]

@jondilly1974, a good charger should be able to show you individual cel stats, but for just a few bucks, you can buy a voltage checker that you plug your balance plug into.
https://www.amazon.com/Readytosky-Battery-Voltage-Precision-Indicator/dp/B073558SN6
This is just one example. You definitely don't want to get in the habit of not balance charging. Your going to shorten the life span unnecessarily. I would also try a total restart on the esc, and carefully check the settings. Your lvc might be set too high, so restoring it to factory defaults would be one other place to start. Hopefully you get this all sorted out, and enjoy the long run times those batteries have to offer.

I bought a Hitec LiPo Checker at the LHS today when I went to buy my Reaction 4S 5000mah 50C pack. How close should the cells be?

1) PH 3S 5200 50C 3.79-3.94-3.96
2) PH 3S 5200 50C 3.81-3.80-3.79
3) Ovonic 3S 7600 50C 4.21-4.19-4.22

I need to run the Ovonic down for storage real quick. Gonna test out this replacement spur that I just plopped in.

That charger you have will show you individual cell stats. Just push the right arrow while it's charging and it'll show you all the cells and their voltages. Just gotta play around with the buttons while you're charging to see what it's capable of. The only downside of the TB6B is it's only rated at 50w for charging. Your 7600mAh lipo must take a long time to charge.

I was not aware that it did that. I will try that next charge. ??????

Edit: Ovonics is now showing 3.69-3.68-3.69 and lasted about 10 mins of hard driving down my street from a 4.2 charge.