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Thread: Lipo questions- run times, balance taps, running in parallel, etc.

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Old 03-12-2011, 11:50 AM   #1
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Default Lipo questions- run times, balance taps, running in parallel, etc.

I'm looking to buy a couple Lipo batteries and had a couple questions. I've got two different rigs I plan on running them in. Space is at a premium so under 1800mah sized packs look to be the ticket.

Axial rig with 10t puller, 7954sh servo, CC bec, MM ESC with 12g wires
Berg with 35t HH motors with 12t, 5995 servo, CC BEC, Punk dig, MM ESC with 12g wires

#1. I'd like to get as much run time out of them as possible, would I be better off using a single 1800mah 3s pack, or two smaller 1000-1300mah 3s packs? A single pack really would be ideal for packaging reasons.

#2. Can I run two packs in parallel with a Y harness on a MM ESC and still be safe with the built in low voltage cutoff?

#3. What kind of run times can you typically expect from those sized packs? I would get roughly 45-50 minutes from a 7.2v 3000mah nimh pack but have never ran lipos and never more than 7.2v and never MOA.

#4. I've got a EOS 0606i charger, will the balance tap on the packs from hobbyking.com work with the stock tap that came with my charger (the battery descriptions do not say what brand taps they have and I don't know whats standard, remembered there was 3 or 4 main types of connectors)? I was looking at the Rhino and Turnigy packs in particular.

I appreciate any help I can get. Searching for "run time" and "balance taps" didn't turn up much related.

Thanks in advance.
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Old 03-12-2011, 12:28 PM   #2
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The balance plug for the Turnigy packs is JST-XH and I believe the Rhino's are the same. You'll need the correct adapter for your charger. Jason at Krawler Hobbies/Krawl Off-Road should be able to help you out with that:
http://www.krawloff-road.com/store/i...tegory&path=35
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Old 03-12-2011, 01:59 PM   #3
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i dont know if this will help or not , but i run a 1300 mah 3s with a 35t motor and i get about an hour of run time .
dimensions are
2.750 long
1.250 wide
.750 thick
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Old 03-12-2011, 03:48 PM   #4
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I would expect at least an hour from a 1800mah pack so long as you're not full throttle bashing everywhere.

I'm getting 1hr-1.5hrs out of a 1500mah pack with a 45t motor.

EDIT: Running in parallel doesnt effect them that much. But you have to make sure that you always do it. As if one pack has more cycles on it then the other they will discharge at slightly different rates possibly causing a pack to go under 3v a cell.

Last edited by WIDELOAD; 03-12-2011 at 04:08 PM.
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Old 03-13-2011, 06:36 AM   #5
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Quote:
Originally Posted by wonder squirrel View Post
I'm looking to buy a couple Lipo batteries and had a couple questions. I've got two different rigs I plan on running them in. Space is at a premium so under 1800mah sized packs look to be the ticket.

Axial rig with 10t puller, 7954sh servo, CC bec, MM ESC with 12g wires
Berg with 35t HH motors with 12t, 5995 servo, CC BEC, Punk dig, MM ESC with 12g wires

#1. I'd like to get as much run time out of them as possible, would I be better off using a single 1800mah 3s pack, or two smaller 1000-1300mah 3s packs? A single pack really would be ideal for packaging reasons.

#2. Can I run two packs in parallel with a Y harness on a MM ESC and still be safe with the built in low voltage cutoff?

#3. What kind of run times can you typically expect from those sized packs? I would get roughly 45-50 minutes from a 7.2v 3000mah nimh pack but have never ran lipos and never more than 7.2v and never MOA.

#4. I've got a EOS 0606i charger, will the balance tap on the packs from hobbyking.com work with the stock tap that came with my charger (the battery descriptions do not say what brand taps they have and I don't know whats standard, remembered there was 3 or 4 main types of connectors)? I was looking at the Rhino and Turnigy packs in particular.

I appreciate any help I can get. Searching for "run time" and "balance taps" didn't turn up much related.

Thanks in advance.
1 The two smaller packs will run longer with a pair of 1300 being the longest.
2 Yes , esc will not know how many packs are parallel.
3 On the identical set-up I estimate 15-20 minutes from a 3sx1800 mah pack.
4 IDK , but make sure to check pin order on many boards (they are reversed)
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Old 03-13-2011, 07:05 AM   #6
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I basically agree with the post before mine.

Runtime is based on "mah", the more you have the longer you run assuming same pack voltage (3S compared to 3S, etc). If you had 2 1000mah or 1 2000mah pack runtime would be essentially be the same (maybe a tiny bit better due to less connection losses).

I would only expect you to get less than 1/2 hour runtime based on size of battery.
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Old 03-13-2011, 11:24 AM   #7
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Those are big differences in run time, roughly 15 minutes 1 1/2 hours

I'm going to have to get some ideas on how to mount the bigger battery or all of the electronics
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Old 03-13-2011, 03:05 PM   #8
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I'm running a 2.2 Bully MOA, 2 ~35T motors, CC MambaMax ESC, HiTec 7955 steering servo, CC BEC (@ 6.5VDC) & 1300mah 3S 40C Lipo's.
I get around 15 minutes of run time, but that is rather "spirited" driving with big binds.

Use this as a guide.
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Old 03-13-2011, 04:54 PM   #9
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Quote:
Originally Posted by Charlie-III View Post
I'm running a 2.2 Bully MOA, 2 ~35T motors, CC MambaMax ESC, HiTec 7955 steering servo, CC BEC (@ 6.5VDC) & 1300mah 3S 40C Lipo's.
I get around 15 minutes of run time, but that is rather "spirited" driving with big binds.

Use this as a guide.
I appreciate the help guys. I'm going to have to see if I can figure a way to mount the electronics or just buy like 6 small packs
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