c- rating
10-24-2012, 04:25 PM
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c- rating
I am running two 6-cell batteries in series in one of my bigger planes and was wondering about the C-rating I am useing. I am looking at some batteries that have a 65 c rateing and I am presently running a 25 c rating. What are the advantages and diss-advantages if any.
10-24-2012, 04:37 PM
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RE: c- rating
65C will give you more power (a little bit) and run cooler. They are probably heavier and may allow you to charge them much faster. Generally it is stated to buy a "minimum" certain rating so if 25C is ok then buying a 65 C may be considered a waste by some. It surely won't hurt anything though.
10-24-2012, 04:52 PM
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RE: c- rating
Well let me explain what I am looking at. I am flying a 12 ft Telemaster. Currently running two 5000 Mah 5 cells 25c in series. (10 Cell) Have been told by the manufacturer that 12 Cell would be better and I am looking at getting 4 4400 Mah 60 c 6 cells. 2 ran paralel and then in series. I had to put in a little over 2 pounds of weight in the nose to balance it and plan on taking that out and using the batteries to make up the difference. More flight time and getting away from dead weight is my goal.
10-24-2012, 05:56 PM
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RE: c- rating
A great idea inmop. Removing weight and making it up in extra battery. Could give you the more power AND longer flights at the same time. That's always good. You may also consider going to a larger capacity rather than a larger "C" rating. (or maybe that's what your doing)
10-24-2012, 07:10 PM
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RE: c- rating
More Mah was my intention. But I found a great buy on the 60c batteries and it will increase the mah as well. I was worried about the ability of these batteries to give more amperage. I have heard that Deans plugs are only rated at 85 amps and I think that the arming plug is less than that. I think my set-up will pull close to 100Amps on take-off especially if it has the bomb-bay loaded.
10-25-2012, 04:54 AM
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RE: c- rating
The batteries won't push more amperage, they will just deliver more when asked without damage.
Its really nothing more than a measure of the internal resistance of the battery.
Edit: Something else to note, manufacturers C ratings are often...shall we say....optimistic.
Its really nothing more than a measure of the internal resistance of the battery.
Edit: Something else to note, manufacturers C ratings are often...shall we say....optimistic.
10-27-2012, 06:33 AM
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RE: c- rating
ORIGINAL: BarracudaHockey
The batteries won't push more amperage, they will just deliver more when asked without damage.
Its really nothing more than a measure of the internal resistance of the battery.
Edit: Something else to note, manufacturers C ratings are often...shall we say....optimistic.
The batteries won't push more amperage, they will just deliver more when asked without damage.
Its really nothing more than a measure of the internal resistance of the battery.
Edit: Something else to note, manufacturers C ratings are often...shall we say....optimistic.
10-27-2012, 09:40 AM
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RE: c- rating
As said most manufacturers are overly optimistic with their C rating claims.
Over on RC Groups several posters have developed an easy test for true C rating.
They say and are proving that it is physically impossible to have a C rating much over 35.
So these manufacturers are misleading us quite a bit.
Have said that, a higher C rating will deliver the power faster, not being restrained by a higher IR.
But it is always wiser to use the lowest C rating your setup can use to your satisfaction.
It is cheaper and the packs weigh less.
Over on RC Groups several posters have developed an easy test for true C rating.
They say and are proving that it is physically impossible to have a C rating much over 35.
So these manufacturers are misleading us quite a bit.
Have said that, a higher C rating will deliver the power faster, not being restrained by a higher IR.
But it is always wiser to use the lowest C rating your setup can use to your satisfaction.
It is cheaper and the packs weigh less.
10-27-2012, 10:43 AM
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RE: c- rating
I would say its not wiser to use the lowest c rating. Might be cheaper, to start with, but c ratings (as agreed by most/all) are over exaggerated. Best to get a C rating that gives constant current about say 25% more than necessary.
10-27-2012, 01:39 PM
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RE: c- rating
From what I have learned . 1. The c-rating on the front of the battery has nothing to do with how many amps to CHARGE. That for one I am sure will be debated but as for me it is set at 1 or 2 c. 2.To find your 1 c rate: Mah/1000=1c 3. Being as the ratings on the batteries are exagerated most of the time I am going to go with 75% as a safe max draw so Mah/1000x[rated c]x.75= max safe amp pull from motor. Does that make any sense??
10-27-2012, 04:59 PM
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RE: c- rating
No, I know what the c rate means now. No matter what the discharge rate is that is listed on the batteries the charge rate is always 1-2c for me. I know alot of people that think the discharge rate corresponds to charge but they seem to end up with the puffed batteries. I did quite a bit of research on it and think I will stick with the 1-2c charge rate. Which is figured from the Mah. 1000 Mah gets charged at 1 amp most of the time and at the most 2. Most of my batteries say [on the back] "never exceed 5c charge rate". 5 is a little high for me.
