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Old May 14, 2012, 12:23 PM
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1 is to turn and 2 is to burn! as we say so its easy to remember! LOL
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Old May 14, 2012, 05:29 PM
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that makes it impossible to forget lol, i am all back together now but i didnt get a pad of double sided tape to mount the esc when i got my new esc cant seem to find it at walmart have to check at target or something i guess
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Old May 14, 2012, 05:54 PM
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Originally Posted by Rellik View Post
that makes it impossible to forget lol, i am all back together now but i didnt get a pad of double sided tape to mount the esc when i got my new esc cant seem to find it at walmart have to check at target or something i guess
Go to auto zone or any car parts place and get 3m molding adhesive tape..its nice stuff.
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Old May 14, 2012, 06:12 PM
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Or look for the gray 3M mounting tape with the red backing. They used to sell it at Target, but now I have to get it from an auto parts store.
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Old May 14, 2012, 07:40 PM
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my second job is at pepboys im a tech but the stuff they have isnt great but im going to try it
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Old May 14, 2012, 10:45 PM
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chris, i just about have everything back together , i was testing everything out on the bench, and the esc allowed my lipo to go below save voltage, using the card it says you can set any where from 0-49.9v what should it be set to for a 2s lipo to keep it from going past safe voltage?
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Old May 15, 2012, 02:05 PM
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You can set it 3.0 volts per cell so that's 6V. Any less would damage your packs and also if you running to the end of the pack be sure to check temps and adjust the LVCO up to 6.2 or 6.4 as needed to keep your packs safe.
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Old May 15, 2012, 03:58 PM
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So I hooked my batteries up to the charger and it said voltage to low and said hit + to recover so I did that and then charges it, on pack has about 6-10 cycles on it and the other is fairly new 2-3 cycles do you think there both Ruend or will they be ok, no swelling or heating seen
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Old May 15, 2012, 04:17 PM
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Ok since Im not there to see it I'll ask the usual questions first.
Did you match the cell count to the charge settings? So your charging a 2S pack on the 2S setting correct? Otherwise a peak charged 2S can fool a charger into thinking its a discharged 3S pack.
On the ESC did you change any of the LVCO settings? What is it set to prior to these batteries being so low?
How did you store the batteries and how long did you store them? Fully discharged?

When you ran the bike how hot did the packs get when you pulled them each out of the bike?

Normally if the packs are really hot and fully discharged then left to sit they will regenerate some charge and then stabilize. If they do this they can be swollen but not all packs do depending on generation and C rate. If your packs are stored with very little charge and allowed to sit for extended periods then they can drop voltage quickly causing a cold failure. In this case most packs will not swell they are just dead.

Always disconnect your packs from the ESC. The circuit can still drain a pack when turned off and this will cause a cold failure for sure.

Look at these different reason for your packs to be very low and see what makes sense for your situation.

Let me know if that helps otherwise there could be another cause.
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Old May 15, 2012, 04:28 PM
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Another note for all of you guys, just FYI;

You can set the LVCO to coincide with the packs peak temp when you pull the pack out of the bike. In other words the peak temp, max run time and best performance should all come together at the same time. You can adjust the LVCO to help keep the pack from over stressing as it nears the end of the capacity.

LiPO's will heat up more during the last part of the discharge than they do in the beginning or middle part of their discharge. Setting the LVCO higher will keep a pack from dipping to low and causing extra heat, failure or damage to the pack.
Yes this may shorten the run time but the investment you have in packs will be better taken care of.

For the VMX I suggest you use the highest C rate and capacity you can find. The packs will not suffer for it in the VMX. Lower performance packs will be worn out quickly if your an aggressive rider.
On the new MM450 we get away with using the lower end packs, 25C 3200mah, and see great run times and performance. The two bikes use power differently due to the loads.
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Old May 15, 2012, 10:44 PM
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Quote:
Originally Posted by Chris Nicastro View Post
Ok since Im not there to see it I'll ask the usual questions first.
Did you match the cell count to the charge settings? So your charging a 2S pack on the 2S setting correct? Otherwise a peak charged 2S can fool a charger into thinking its a discharged 3S pack.
On the ESC did you change any of the LVCO settings? What is it set to prior to these batteries being so low?
How did you store the batteries and how long did you store them? Fully discharged?

When you ran the bike how hot did the packs get when you pulled them each out of the bike?

Normally if the packs are really hot and fully discharged then left to sit they will regenerate some charge and then stabilize. If they do this they can be swollen but not all packs do depending on generation and C rate. If your packs are stored with very little charge and allowed to sit for extended periods then they can drop voltage quickly causing a cold failure. In this case most packs will not swell they are just dead.

Always disconnect your packs from the ESC. The circuit can still drain a pack when turned off and this will cause a cold failure for sure.

Look at these different reason for your packs to be very low and see what makes sense for your situation.

Let me know if that helps otherwise there could be another cause.
I was not running the bike I was just testing everything out on the bench before I took her out, i have a thunder power 610 charger, if I put the cell count wrong it will beep and prevent any charging, nether battery was hot at all not even warm. It did a recovery an then I did a 50% charg (storage mode on the charger)

I actually set the LVCO at 3.3 (don't ask why ) What should it be set at for a 2s?
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Old May 16, 2012, 04:30 AM
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Rellik, I had to program esc without a card. Looking at the esc manual, I set the "cutoff threshold" to max I could, which is 3.1v (and per cell!!). This manual says it will determine the "Low Voltage Protection Threshold" by taking # of cells * cutoff value. So if I run 2s, LVC better be 6.2 total, and at 3s its 9.3.

HOWEVER, I grabbed your programming card manual and its even worse than the esc manual. It describes the value as "proper cutoff voltage according to cell quantity in range of 0.0-49.9v". huh

In other words, I have no idea if the value you set with programming card is per cell or the total LVC with cell count included. All it had to say was "Set the lvc PER CELL"
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Old May 16, 2012, 04:55 AM
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Hi Chris, when do you think the new MM450 will be available in shops in the UK?
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Old May 16, 2012, 06:54 AM
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Quote:
Originally Posted by JohnnyMc View Post
Rellik, I had to program esc without a card. Looking at the esc manual, I set the "cutoff threshold" to max I could, which is 3.1v (and per cell!!). This manual says it will determine the "Low Voltage Protection Threshold" by taking # of cells * cutoff value. So if I run 2s, LVC better be 6.2 total, and at 3s its 9.3.

HOWEVER, I grabbed your programming card manual and its even worse than the esc manual. It describes the value as "proper cutoff voltage according to cell quantity in range of 0.0-49.9v". huh

In other words, I have no idea if the value you set with programming card is per cell or the total LVC with cell count included. All it had to say was "Set the lvc PER CELL"
i think the card sets it as a total and that's where i think i messed up b.c i set it for 3.3v and i was thinking the 6.6 total v would be the lvco but since that didn't work im going to set to 6.3 and see where that gets me, i know the old on use to cut off at 3v/cell but this new one i guess wasn't programmed properly before being send back to me. one of the 4 screws on the esc fan was also stripped when i got it but i waited 2 months get get my esc back so im going to just deal with it lol
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Old May 16, 2012, 11:26 AM
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Post Falls, ID United States
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Using the card the value is the total of the cell count value. Set it for 6.2V and try it again.
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