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Everything You Wanted To Know About Electric Powered Flight

Old 07-04-2011, 11:29 PM
  #201  
Scott Jackson
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Default Motor Installation Angle

Thanks Ed, I'll let you know what we find.
Regards, Scott
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Old 07-05-2011, 05:04 PM
  #202  
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Originally Posted by mred View Post
I don't blame you for feeling frustrated, I would be too if I couldn't get help from the Pro's at the club.

First of All, you have to understand what the down thrust and right thrust is all about. Down thrust is to counter the lift of the wing on a high lift wing. With a flat bottom wing, it has a large amount of lift and to keep it from climbing under power, you need the down thrust to keep the plane flying level. This is only set for one speed, as any increase over cruse will give you a climb again. Generally, the cruse speed is not WOT on a plane such as the one you have, so you need to throttle back for cruse. This way, it will have a nice climb under full power and fly level at cruse setting and decend at idle in a nice glide.

Right thrust is there to overcome "P" factor during a climb. That is, the down going blade has more effect then the up going blade in the climb, so you get a left turn induced during a climb. To counter this, you put in right thrust. At cruse speed, it has very little effect, so you can forget about that for straight and level cruse speed.

You say that it had a violent left turn on take off the first time, so you have a warp or twist in the wing some place. Look at the control surfaces. They should all be at or VERY near neutral with the control sticks centered. The gentleman that did your first flight had to put some kind of trim in to counter the left turn, so you should have something trying the turn it right all the time now just to get it flying straight.

Lay your wing on a FLAT surface and gently push it down until it is laying flat on the surface. Look at the trailing and leading edge. They should both be on the surface at the same time, but don't force the wing down flat, just gently push it down. If the trailing edge is up, you have washout and it the leading edge is up, you have washin. Normally, you have washout built into the wing, so check that it is the same on both sides.

If you find a twist in the wing, you can take it out by re-shrinking the covering while holding in a twist in the opposite direction and letting it cool before you let go. You may have to do this a few times and once you get it right, you need to check it again the night before you go flying to make sure it hasn't changed again. After awhile, it will take a set and pretty much stay in there.

Motor offset is the same for any type of power plant you have installed. That does not change just because you are using a motor instead of glow. You are compensating for the thrust of the power plant, not the type you have installed. This is going to be the same regardless of the type of power plant you have installed. You just have a warp somewhere and you need to find it. Some times they can be very hard to see, but I think you will find this one with no problem.

Also check your controls and make sure you have the same movement in both directions. Somewhere you have quite a bit of trim in because of that left turn on takeoff on the first flight. He had to put in right trim in order to get rid of that left turn, so you may not have very much right movement left on the controls. I think your ailerons are trimmed off center quite a bit, so check them and make sure you are close to neutral and they still have plenty of movement for a right turn. That wing is almost flat, so trying to turn on rudder is going to induce a skid. It doesn't look like it has enough dihedral for a rudder turn without using ailerons too. After you get your plane flying right, take the pushrods off the controls and reset the trim on the transmitter to neutral and then adjust your linkages to put the surfaces back where they were with the trim in. This will give you full movement of the servo again.

Let us know what you find and here's hoping you find it quickly.

Ed
What an outstanding post Ed. Your whole post is terriffic but in relation to motors and angles you really hit a whole bunch of nails right on the heads. Thanks!

Having taken a couple of full scale flight lessons, the way it was stated was Throttle is for altitude and elevator is for attitude.

Now, we do things with our RC airplanes that full scale pilots typically would not do, but in a full scale airplane you increase throttle to climb. Ed described it perfectly.
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Old 07-06-2011, 04:12 PM
  #203  
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QUESTION --THRUST LINE
Building up a SKY SURFER/ BIXLER. ARF, It came with their Outrunner motor. I removed this motor, did an up grade from HEADSUPRC. with a more powerful Outrunner motor. Pruchased their plastic motor mount for this motor..
Now, I left the org. motor mount in. There was a center hole in this motor mount which fit a 5/8 dowl rod. Mounted the new HU plastic motor mount on this dowl rod.
shoved the back plate of the new mm flush and FLAT with the org. Motor mount.
Thus, I assume has to be the SAME THRUST LINE AS THE ORG. MOTOR.
I AM ASSUMING THAT MY THRUST line is OK??
What say you all.
Looks Good!
Again, assume first test flight will tell.
WHAT DO ALL OF YOU THINK ???
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Old 07-06-2011, 07:44 PM
  #204  
Scott Jackson
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Thanks Ed. I'm wondering .....I'm using a 40 equivalent electric outrunner motor. There is a lot of spinning mass with no offsetting vertical movement as in a gas/glo motor. Is there a gyro effect I must take into account ?
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Old 07-11-2011, 06:44 PM
  #205  
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Just an FYI, I made some minor updates to the first three articles, deleted some out of date links and inserted a couple of new ones. Just doing some maintenance.
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Old 07-11-2011, 06:46 PM
  #206  
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Originally Posted by Scott Jackson View Post
Thanks Ed. I'm wondering .....I'm using a 40 equivalent electric outrunner motor. There is a lot of spinning mass with no offsetting vertical movement as in a gas/glo motor. Is there a gyro effect I must take into account ?
The rules for thrust angles are simlar to glow and gas motors. The issue is more around the prop than the motor so that would not change much when going to electric. I don't believe the spinning can of an outrunner brushless motor imparts that much torque or gyro effect when compared to the propeller.

I think the wet fuel crowd refers to this as the P Factor.

Typical is 2 degrees down and right thrust angle to offset the P factor. Then you tune from there. Others may have an expanded view on this. I invite them to comment.
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Old 07-12-2011, 01:05 PM
  #207  
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Hi Guys, WoW!! I've been looking at all the "Everything..." information all of you have posted an I'm very greatful to you all.
I'm a guy that's flown nitro planes for about 8 years and have also added electrics several years ago - I love them both.
As happens to us at times - I was given a small box of parts by a fellow club member who tried electrics but decided to stick with nitroplanes. So, at a club meeting, this kind gentleman hands me a box with 4 electric motors and the same number of ESCs.
My problem is that 3 of the ESCs have no markings on them - I don't know thier ratings for amperage. They seem about the physical size of a 20 amp ESC, but how can I tell? I'm aware it's not the size of a ESC that determines the amp load it will handle, but is there a way to figure out what the electronics inside will handle?

Thanks ahead of time for your answers. I think I'll go try to hook it up to my "Castle-Link" and see what my computer tells me. (Is that the answer?) Mike Kennedy - Cincinnati, Ohio
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Old 07-12-2011, 03:14 PM
  #208  
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No markings of any kind? Just black? I don't know of any way to tell what they are. Can you post a photo? both sides of each one might reveal something.
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Old 07-30-2011, 11:34 PM
  #209  
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Good day everyone,
This is my first post (!)

So first, many thanks to Ed for putting this E-Book together.

Very very helpful, I think I read everything in the past few days!
I would like to get back to post 11, battery chargers etc.

Is it possible to have a little write up on specifically battery chargers and how they work.
To make it personal I will tell you what I have. Everyone is welcome to comment on the set-up and offer suggestions, but if we could have a detailed write up on battery chargers that is the goal.

Post 11 is not very specifics and battery chargers have changed sooo much (apparently) in past few years. Also if this could specifically cover LiPo batteries that would be great.

I did read all the warning, dangers etc about the battery what I did not find is information about chargers.

ex.
What features should one look for?
What is the importance of the output 'W' of the charger?
Fan or no fan necessary?

Oh, and I am new to RC, so I will likely have to read everything twice in order to understand 10% of it...
I have been wanting to get involved for about 30 years and just now came around to doing it!

Here is my main bird:
3w.icare-rc.com/magellan_e-xl.htm

Magellan 2.5M
HK SS 35-40A ESC
Turnigy 35-36C 1100kv outrunner
Turnigy S3101S Servo x4
HK 929MG Metal Gear servo x2
10x6 Folding Prop W/hub 40mm/4.0mm shaft
I am not sure about the ESC, it came with the plane but I think it is on the cheap side.
No battery yet, simply do not know what to get size-wise but also maybe separate set for the motor and the Rx+servos?, keeping in mind that I want to keep it as light as possible.

Second is:
3w.rcgroups.com/forums/member.php?u=315473

Thermic 70, almost completed. this is the link to my 'build'.

The Tx is an Airtronic RDS8000, so 2.4Mhz.

I am thinking of purchasing one of the following Battery Charger:

There is this one,
3w.hobbypartz.com/98p-imars-charger-6s.html
Gens Ace i Mars-Charger-A

I like it because it has a com port to upgrade the firmware etc.
I like its look and seems a quality product
I wonder if 100W is a limitation and I cannot find information on that.
It doesn't come with an AC adaptor or temperature sensor.

Then we have this guy.

3w.hobbypartz.com/26p-balancecharger-6200.html
SkyCharger 6200 Multifuction DC Charger

I like the fan
I like 200W (if it matters)
I like that it comes with more cable accessories.
It doesn't have a com port
And doesn't look as sleek as the Ace charger.

And this is when I realized that I really did not understood what was important in a charger and what was not, in fact I do not understand what the spec means

So there you go.
Wow long first post...

P.S. I was not allowed to post links so I had to cheat a bit, hope you can get to the sites...

Sincerely,

Alain
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Old 07-30-2011, 11:46 PM
  #210  
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Humm, somehow my Avatar doesn't show. Oh well maybe it will come up later.
Cheers,

Alain
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Old 07-31-2011, 05:21 AM
  #211  
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First off, I would like to welcome you to the wide wonderful world or confusion..... Also to models and the hobby in general. I believe that you are not allowed to post pictures and such for the first three posts, so one more and you should be good to go.

As to chargers, that is a whole world out there of chargers and it is very easy to get confused at first. Until you learn a little about electrics, you are going to have to depend on advice from someone else and that can get VERY confusing right there. Everyone seems to have their own preferences for everything and chargers are no exception. I can recommend a couple of different chargers, but then you are going to be the one using it, so you will have to pick one in the end.

H610-HotPower-Charger
Specification
Operating voltage: DC 11~18 volts
Charge/discharge power: max. 200/25 Watts
NiCd/MH: 1~18 cells
LiIo/LiPo/LiFe: 1~6 series
Pb: 2~24V
Charge current: 0.1 to 10.0A
Discharg current: 0.1 to 5.0A
No. of cycle: 1 to 5 times
Battery data memory: up to 5 data
Weight: 477g
Dimension: 140*120*33mm
Balance Charge Slot 2-6 cells
No. of Cycle : 1 to 5 times
Battery data memory : up to 10 data

This is the first one I kind of like. One thing you have to know and that is a lot of chargers do not have the proper adapters for all the batteries out there, so you need to find out what kind of plug is on the battery so you can see if they even offer an adapter for that style of battery. The adapter I am talking about it the one that goes to the balance port on the battery. That is the small one with all those small wires on it. The big black and red wires are the discharge leads, or the ones you hook to the ESC to run the motor. Normally you will charge through these and run the balance current through the small set of wires, but some charge through those little wires only. Once you decide on what battery you would like to use, I would stay with that one for awhile just to make life easy, as not all of these plugs are the same.

The plug you use on the big wires will depend on what you want to put on there. Some batteries come with a plug already installed, but most do not. A lot of people like the Deans plug, but I don't. I like the Anderson Power Polls or APP plug. They are a little bigger, but very easy to take apart and easy to plug in, where the Deans are kind of hard. The are really hard to take apart which is why I don't like them.

Using a changer is very easy. All you need to do is read the instruction manual through a couple of times and have it handy to answer any questions you may have regarding hooking up the battery or charging it. One thing I would say right now. Never change a LiPo battery and let it run in a room all by itself. You need to be in that room watching it and NEVER charge in on the wrong setting. They will tell you all about the settings in the manual so read it and pay attention to what you are doing and everything will be OK. With the new chargers it is not common to have fires, but it is still possible. That's why you stay and watch the battery while it is charging. I would also advise you to get some kind of protection for the battery while it is charging. By that I mean a LiPo bag of something that will contain a fire if one decides to be different and catch on fire. I also advise you to charge them outside somewhere, like in the garage is you happen to have one.

Normally it will take you 1 hour to charge a LiPo battery. That depends on the setting and how much you took out of it, but that is normal. Some of the newer ones are faster and will charge in 30 minuets or less.

http://fmadirect.com/downloads.htm Go here to read a manual on one of their chargers and you will see what I am talking about and it will give you a lot of information on each charger.

http://fmadirect.com/faqs.htm GO here and read a lot of questions they answer on the different chargers.

These people have two of the best LiPo chargers on the market and if you are going to be using a LiPo battery, you can't go wrong with either one of these chargers. The 4S will do a 2,3 or 4 cell battery and the 10S will do a 2 to 10 cell battery. In my opinion, these are probably the best chargers on the market and if you can afford one, you can't go wrong with this charger, but remember one thing, they will only charge Lixx batteries. You cannot charge Nicad or NeMahs or PB batteries. You can get one of your cheaper chargers for those batteries.

I have 5 different chargers, so I can charge anything. You don't need that many, but I bought them over a period of 5 years, so the cost wasn't bad at any one time. You don't need 5 chargers, but I started with a cheaper charger and got better ones later as I could afford them and wanted a up grade to a better charger.

http://myhtcdesire.com/tipstweaks/ti...-afraid-to-ask

http://www.masteringvideography.com/...batteries.html

Here are a couple of sites that tell you quite a bit about batteries. These should answer most of your questions, but if you have any after reading this, there are a lot of people here to answer your questions.

That should keep you busy for awhile. Have fun and if you have any more questions ask away. These sites do not answer all questions, but it will give you a good start. Enjoy.

Ed
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Old 07-31-2011, 02:19 PM
  #212  
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Mred provides some good info. Thanks Ed.

Chapters 10 and 11 cover battery and charger basics. If you have not read them take a look.

I agree the Cellpro 4S is one of the best chargers out there. I love mine. The newer Mult does all kinds of batteries.


It is impossible to look at a charger or its specs and know it is a good charger. They all charge.

What makes one charger good and one not is:
* ease of use ( subjective)
* consistent and reliable operation (requires time)
* information it can provide ( displays, memories, etc)
* special features ( storage charge, cold weather charge, others)
* how large of a pack can this charger handle in an acceptible period of time.

The last three can be gleened from specs. The first two require user reports.

This is also true of motors, batteries, radios, receivers, .... pretty much any product. They all look the same on paper. And they all work to some degree or another.

On a personal basis, as I said above, I recommend the CellPro 4S for most small to medium sized electric aircraft pilots.
http://www.usastore.revolectrix.com/...pro-Chargers_2

The one I have would now be called the CellPro 4S Gold. I am going to tell yo what I like about it, not to create an advertisement but to share some insight about features that I find useful.

I find a meter/display valuable. The 4S display gives me a constant status of what is going on during the charge. It tells me current charge level in the form of a "fuel gague". So I can see how far I took the pack down even before I charge it.

I can see what the charge level is of each cell to confirm they are balanced. This can be valuable itool for figuring out if a pack is good or bad. I can see if a pack is out of balance or may have a bad cell. If that cell is way off from the others, there is a problem. This has helped me determine that one of my other chargers was bad as it was not charging the packs evenly. I tossed it as it was a cheapie.

The 4S has recovered batteries charged on other chargers where the charger did not do a good job of balancing. It recovered packs that other chargers could not charge. The CellPro fixed it.

The charger has a temperature sensor that shifts it into a cold weather setting that charges to a little lower charge level so that if you take a fully charged pack from the cold into the warm house the pack will not go over recommended max voltage. As pack temperature rises voltage rises too.

It has a storage charge for packs that I don't plan to use for a long time. This is a preferred storage charge level rather than full charge.

There are available adapters for just about any kind of balance plug you can imagine. Many chargers don't have these so you can't charge any kind of pack. If the balance plugs don't match you can't charge it. I don't have this problem.

The 4S will also charge the A123 packs which are lithium but requrire a different charge cycle.

The 4S multi will do NiCd, NiMh too. Mine does not. I have a Great Planes Triton for NiCd and NiMh.

The current 4S Multi and 4S Gold will charge at up to 4 amps. which means the largest pack I would want to use them for is a 4S 4000 mah pack as a 4A charge rate will take an hour. They will charge 1-4S 6000 mah packs but it will take more than an hour, other than that they will work fine.

With its monitoring features it can charge smaller packs at up to 3C rates if they are rated at 20C or higher. This means that it will charge the typcial 1300 mah pack that is rated at 20C in about 20 minutes and do it safely. Or it could charge your 2000 mah pack in about 30 minutes.

Typically if I were running Lipos of more than 3500 mah or more than 4 cells I would look for a charger that can provide higher charge rates, like the Cellpro 10S or the Powerlab 8. Both are much more expensive but if you are playing with these bigger planes and bigger packs then the cost is well justified. Those batteries can get pricy and you want a quality charger to charge them.

OK, I know it reads like an advertisement but the goal was to give you a view into what I like about this charger. And it gives you a view into when I would look elsewhere.

I am sure there are other quality chargers out there. Go search on Lipo chargers.

I do not want this turned into a battery charger review thread however brief posts with a reference link would be fine. Be sure to include a link to info about the charger or a thread about that charger.

Only comment about a charger that you own. If you don't own it and have not used it then you can't recommend it here.

I want to keep this tread more general. So if the posts start to build up about this or that charger, I will delete them. If you see a post about a charger, PM the author and take your discussion off-line.

For the electric pilot the battery charger is a most critical component of your tool box. It deserves careful selection and probably a bit more dollar investment than buying the cheapest one around. Don't buy a charger because it is cheap. But cheap chargers are not always bad. I have a bunch that I got in RTF packages and they all work, but I make sure that each of those packs gets onto the CellPro 4S from time to time to make sure it is balanced and so I can get a good idea of the pack's condition. You can more safely use the cheap chargers if you have a quality charger that can overcome some of the cheap charger flaws.

Last edited by AEAJR; 07-31-2011 at 03:11 PM.
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Old 08-03-2011, 01:48 PM
  #213  
adyonfire4
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thanx for the help really useful stuff.
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Old 08-04-2011, 08:29 AM
  #214  
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First I want to say thx for the replies!
I was not ignoring the thread I was away in the trails for a few days so no access there of any kind!
I will read all the links and get back to you guys!

The first thing that pops-up is that I do not understand (for example) the spec that you presented for the charger in your reply or the functions that are described in your reply (Ed) so I will read everything and hopefully the fog will lift.

Cheers,
a.
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Old 09-17-2011, 03:31 PM
  #215  
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Have a question that I have not seen posted so I'll ask it here (here being the first and only forum discussion that I have not only read, but re-read a number of times, GREAT STUFF!).

When I first got into electrics (flying glow since the mid 1970's) I received retirement gift certificates to FMA Direct and I purchased a number of their LiPo batteries and a couple of the Cellpro Mulit4 chargers. Being new to electrics I thought nothing of the fact that they charged only thru the balance connector. As I discovered the fun electrics can be, I wanted to be able to charge my batteries at the field. Not wanting to take the Cellpro Multi4's into a field environment I looked at a Triton Jr. that I already had. I re-read the manual for the Triton Jr. and got to the section where it states that if your LiPo battery has a balance connector, you MUST charge that battery thru the balance connector and not thru the main battery output leads.

At this point it was cheaper to purchase an Accucel-6 from Hobby King than get a balance add on for the Triton Jr. When I received the Accucel-6 I was surprised to see that to charge LiPo batteries I needed to connect BOTH the balance connector AND the main battery leads to the charger.

OK, after all of that here's the question. In the forum threads I read that some folks balance charge their LiPo batteries all the time, some folks balance charge them once in a while and some folks never balance charge.

When you don't balance charge, does that mean that you just connect the battery to the charger via the main battery leads and don't connect the balance connector, or do you connect everything and the "non-balance" charge is a function of settings in the charger. Just wondering if I could have used the Triton in the field and just charged thru the main battery leads.
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Old 09-17-2011, 04:24 PM
  #216  
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For the highest level of safety you should always connect the balance plug no matter which charging mode you plan to use. This way you can monitor individual cell voltages and the charger will automatically stop the charge if any cell goes above 4.2 volts. Not connecting the balance plug sends you back to the dark early years of LiPo battery use when charging fires were more common.
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Old 09-18-2011, 03:12 AM
  #217  
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Hi everyone,
I am still following this thread it is just full of information!
If someone feel like starting a thread specifically for chargers please do so and post a link in here.
I did not want to hijack the thread with my original question on chargers.

Cheers,

a
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Old 09-18-2011, 03:50 AM
  #218  
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Originally Posted by Homer712 View Post
Have a question that I have not seen posted so I'll ask it here (here being the first and only forum discussion that I have not only read, but re-read a number of times, GREAT STUFF!).

When I first got into electrics (flying glow since the mid 1970's) I received retirement gift certificates to FMA Direct and I purchased a number of their LiPo batteries and a couple of the Cellpro Mulit4 chargers. Being new to electrics I thought nothing of the fact that they charged only thru the balance connector. As I discovered the fun electrics can be, I wanted to be able to charge my batteries at the field. Not wanting to take the Cellpro Multi4's into a field environment I looked at a Triton Jr. that I already had. I re-read the manual for the Triton Jr. and got to the section where it states that if your LiPo battery has a balance connector, you MUST charge that battery thru the balance connector and not thru the main battery output leads.

At this point it was cheaper to purchase an Accucel-6 from Hobby King than get a balance add on for the Triton Jr. When I received the Accucel-6 I was surprised to see that to charge LiPo batteries I needed to connect BOTH the balance connector AND the main battery leads to the charger.

OK, after all of that here's the question. In the forum threads I read that some folks balance charge their LiPo batteries all the time, some folks balance charge them once in a while and some folks never balance charge.

When you don't balance charge, does that mean that you just connect the battery to the charger via the main battery leads and don't connect the balance connector, or do you connect everything and the "non-balance" charge is a function of settings in the charger. Just wondering if I could have used the Triton in the field and just charged thru the main battery leads.
Why would you not take your Cellpro 4 chargers to the field? That is what they are made for.

OK let's talk chargers. They are so integral to electric flight that the should be discussed here. What I don't want to get into is a discussion about this brand vs. That brand.

When you charge through the battery connection you charge the pack to a pack voltage, but the individual cells may not be evenly charged. The pack might be out of balance. The function of the balance port is to charge and monitor the cells individually. This gives you the best performance and life from your LiPo pack.

Chapter 11 ( post 11 http://www.wattflyer.com/forums/show...6&postcount=11 ) discusses chargers and the different types.

What you discovered is balancing chargers vs. chargers with balancers.

The Cellpro is an example of a balancing charger. It only charges through the balance plug. Essentially it charges the cells individually on every charge.

The one you bought from Hobby King is a lipo charger with a balancer. Charging is happening through the battery port. But a balancer is bleeding down individual cells so that they come down to the same charge as the other cells.

Which is better? They both accomplish the same thing, giving you a balanced pack. They just do it in a different way.

Then there are lipo chargers that only charge through the battery port. My original Triton charger is this type. It charges the whole pack and has no way to balance the individual cells. You would have to get a separate balancer to balance the pack.

My preference is the CellPro 4 type, a balancing charger. But I do occasionally charge my lipos with the Triton, a non-balancing charger. However I make sure they get on the CellPro 4 every few charges so that they get balanced.

It should be noted that cells get out of balance over time. After several charges on a non-balancing charger there is a chance that a small difference in voltage between the cells could occur. Over time that can start to build up. This can rob the pack of its life and its power.

Hope that was helpful.

Last edited by AEAJR; 09-18-2011 at 02:37 PM.
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Old 09-18-2011, 02:34 PM
  #219  
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AEAJR,

As always, your response makes the issue clear. Thank you.
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Old 09-24-2011, 09:29 PM
  #220  
munkee
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Great resource I will be reading through all of this over the next few days. Great to have all this info in one place when you are just starting out =]
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Old 11-27-2011, 09:59 PM
  #221  
repinfl
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I purchased a Great Planes Eletrostik ARF that came with an Electrifly Silver Series 45 amp brushless ESC and a Great Planes Rimfire 42-40-1000 outrunner brushless motor. I also purchased there ElectriFly 11.1V 3200mAh 20C BP Series LiPo Battery at the same time. Everything worked GREAT! Later I purchased some batteries fron Hobby King, (Turnigy and Zippy)
trade names of same type as the ElectriFly but much cheaper! When I try to use these I have a problem. If I advance the throttle very slowly all is OK BUT when I advance the throttle quickly the motor stops and there is a LOUD growling noise. When I reinstall one of the ElectriFly batteries, and I have more that one, they work with no problem. HELP! Thanks, Robert
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Old 11-28-2011, 02:05 AM
  #222  
mred
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You didn't say what kind of battery you got. What is the "C" rating of the batteries you bought from China?? I hope you got the 30C or 40C batteries, because they have 10C batteries and if you got one of these you are in trouble. Your motor is able to run at 45 Amps and a 3.5 Amp battery will not handle that very well if it is a 10C battery. A 20C battery will handle the amp draw, but you would be better off with a 30C or 40C battery. The "C" rating is very important as to how the battery reacts to the amp draw from the motor. The higher the "C" rating the better it will perform and the more amps it can put out. Let us know what the "C" rating of these new batteries are and maybe we can help you a little more.

Ed
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Old 11-28-2011, 04:02 AM
  #223  
mred
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I would like to address a couple of issues about charging in general. First, you CAN charge through the discharge leads and this is not a problem IF you don't get an imbalance in the cells. First of all, this is not going to happen in one discharge cycle unless the battery is a very new battery and has not been used yet or is bad to start with. You should cycle a battery 4 or 5 times before using it and while this is a pain, it really helps the battery form and to function better over the life of the battery. One of the first battery chargers I bought was a Triton and it will not balance a battery, so I bought a small battery balancer to go with it. It cost me all of $11.00 for that and it works great. You charge through the discharge leads while hooking the balancer to the balance leads and it will balance the battery while it is charging. The The Turnigy Accuell-6 does the same thing, but it is all built onto one unit. It is going to take longer to charge a battery using one of these chargers then a normal charger that does not balance a battery while charging, because it is discharging the battery at the same time it is charging it.

I have never heard of a battery going bad on one charge cycle unless it is a new battery and has a bad cell from the start. A cell will slowly go down on it's charge over use and several cycles and while this will not really hurt the battery if it is a good one, it will get worse over time and then it can hurt the battery. An imbalance of .1 volts is not real bad, but it will not get any better unless you balance the battery with a balance charge.

When a battery is fully charged, each cell is 4.2 volts and they should all be the same. If one cell is low, then the other 2 will charge higher to make up the difference. This is because the charger sees voltage when it is charging. If one cell is reading 3.8 volts when fully charged, then the other 2 cells must charge higher to get an over all reading of 4.2 volts per cell. For a 3 cell pack this is 12.6 volts. If one cell is reading 3.8 volts, then the other 2 will read 4.4 volts per cell to make up the difference. This is not good. If you run your pack down to 3.2 volts per cell at cut-off, then you wind up with one cell that is under 3 volts and this is not good either. Sooner or later you may get a fire out of this battery pack because of this imbalance and that is VERY not good. ( I know, bad English ) Mine all charge within .01 volts of each other and this is where they stay all the time. I have checked my batteries with a FLuke DVM and my Cell Pro 4S is right on the money.

Charging a battery through the balance leads is the best way to charge a battery. This is done in chargers like the Cell Pro 4S and other chargers like this one. Mine does NOT charge anything except for LiPo's and while it doesn't have the hard case around it, I do take it to the field with me and have yet to hurt it. I always use it before any other chargers, unless I am in a hurry and need to charge more then one battery at a time. I only have one of these chargers, so I use another battery charger if I am charging more then one battery.

Now as to charging in one hour. This may or may not happen. It all depends on how much the battery was discharged before you put it on the charger. A normal charge is considered a one hour charge, but that is not necessarily true. If the battery is completely flat, then it will charge to 80% of capacity in one hour. The rest of the charge will take longer and depending on where the cut-off voltage is set at the factory, it may take another two hours or 10 minuets. You cannot change the cut-off voltage as it is set by the factory in the software and it is not easy to change. You would have to change the software to change it.

I bought one battery and had a cell that would NOT charge up to 4.2 volts and would go under 3 volts if I let it. I called up the man I bought it from and he had a replacement in the mail that afternoon before I even sent my old one back in. That is the kind of service you will never see out of China.

To sum up, if you can balance charge, all the better. If not, then do a balance charge every 5 or 6 cycles and let it go to cut-off so the battery is fully charged and balanced. If possible, get a charger like the Cell Pro 4S to use all the time. If not that one, then get one that has a balance port in it to balance while charging like the Turnigy Accuell-6. If you don't have one of these, then get a balancer to go with your charger so you can balance your batteries. In short, ALWAYS balance charge your batteries if possible. If it is not possible on every charge, then do it on the 5th or 6th charge anyway. Just don't go very long before balance charging your batteries.

I know, there are people out there that have never done a balance charge and have gotten away with it. Let me ask you one question. Is your house worth keeping? If it is, then balance charge, or take them outside to charge and store. They got away with it simply because the new batteries are great and made much better then the old ones. Sooner or later you will hear about one of them setting one on fire and hopefully they won't do it in the house.

Ed
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Old 11-28-2011, 05:48 AM
  #224  
Turner
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The risk of fire has more to do with the charger used than with whether or not you balance. A charger like the Triton, that cannot balance, has no way to monitor the voltage in each cell, and ends charge based on pack voltage alone is a real risk. Using a balance charger with the balance lead connected will stop the charge if any cell exceeds 4.2 volts, for LiPo, even if you choose a charge mode that does not balance. This is much safer.

Yes, a knowledgable person can use the Triton with a balancer and close attention and do so safely but when buying a charger for LiPo batteries always look for a balancing charger and always connect the balance lead for best safety.
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Old 11-28-2011, 03:00 PM
  #225  
repinfl
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mred "You didn't say what kind of battery you got. What is the "C" rating of the batteries you bought from China??"

I tried to order the same as I purchased from Great Planes i.e. 3200 mah 11.1V 20C but one is
a "NANO-TECH" 3300 mah 35C and it does the same thing. I might just purchase another battery from GP and see but I assume there batteries come from China also. Thanks for the help...Robert
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