Wattflyer RC Network: RC Universe :: RCU Magazine :: RCU Forums :: RCU Classifieds :: RCU User Reviews :: RCU YouTube
Home Who's Online Calendar Today's Posts RealTime Post Spy Mark Forums Read
Go Back   WattFlyer RC Electric Flight Forums - Discuss radio control eflight > Electric R/C Airplanes > Beginners
Register Members List Wattflyer Extras Articles Search Today's Posts Mark Forums Read Social Groups

Beginners New to e-power flying? Get the low down in here from experienced e-power RC pilots!

Thank you for your support (hide ads)
Reply
 
Thread Tools Display Modes
Old 10-16-2013, 09:03 PM   #1
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default New Apprentice 15e, what accessories?

Hey everyone, I finally decided to jump into the RC Airplane world. This has been a small dream of mine for the past 20 years and decided to pull the trigger.

I'm going to purchase my apprentice 15e SAFE tomorrow and was wondering what else I need? I know it has everything in the box but I would like more batteries and faster chargers. What extra batteries and chargers should I consider for longer flying time and faster charging?

Any help would be much appreciated.


~ Chris
MKE-Flyer is offline  
  Reply With Quote
Old 10-16-2013, 09:37 PM   #2
xmech2k
Ya got any Beeman's?
 
xmech2k's Avatar
 
Join Date: Apr 2009
Location: San Diego, CA
Posts: 2,702
View xmech2k's Gallery21
Thanked 254 Times in 252 Posts
Club: CVMRCC, SEFSD
Awards Showcase

Scratchbuilders Award  1kW  Outstanding Contributor Award 
iTrader: (0)
Friends: (7)
Default

Hi Chris, and welcome to WF. You'll enjoy the Apprentice. I still have my original non-SAFE one, and enjoy flying it now and then.

As far as extra equipment, I'd just recommend an extra battery or 2. The stock charger is a little slow, but I find it best to charge at home the day before I go fly, and not bother with charging at the field. (Unless you're having a great LONG day at the field!) A better charger I think will save possibly 20 minutes on a charge, depending how far you run the battery down. To charge even faster things get a bit more complicated and would take a while to explain. To get started, a basic balancing 80w charger should serve you well for several years, unless you plan on moving on to bigger, higher power planes quickly. For a little more, there are nice 200w chargers available. I'd just recommend to be sure they are ones that you have to plug in the balance plug as well as the main connector so the charger can at least tell if you told it the right cell count. (I just watched a guy try to burn down his car recently this way.)

Here's some great reading material to learn about the batteries and such: Everything You Wanted to Know About Electric Powered Flight.

A box of rubber bands for the wings on the Apprentice is a good idea. The stock ones seem to deteriorate quickly. (They all deteriorate in the sun.) Use a all the included ones to secure the wing. I hear people who don't and experience the plane pulling up sharply in dives and other maneuvers because the front of the wings lift due to too few rubber bands. A spare prop or 2 is good to keep around so your flying doesn't get cut short by something that simple.

Just be sure to read the instructions and understand what SAFE can and cannot do. Out of curiosity, do you have any previous experience? Any aeronautical knowledge or simulator time? Or do you have someone who flies already and will help you get started? Some people can manage this right away, others take some time.

Good luck!
xmech2k is offline  
  Reply With Quote
Old 10-16-2013, 10:10 PM   #3
dereckbc
Member
 
Join Date: Jun 2013
Posts: 331
Thanked 6 Times in 6 Posts
iTrader: (0)
Friends: (3)
Default

I have an Apprentice 15e with SAFE. Be aware it is known to have some glitches which can cause loss of control.

The two things I highly recommend is as many battery packs as you can afford. I do not recommend buying any of the E-Flite batteries as they are expensive and low quality. Some very good ones are Glacier available from EP Buddy. I use both there 3S 2600 ($26) and 3S 3300 ($33). Both are about half the price of the E-Flite pack, have higher charge and discharge rates, and will last a lot longer.

Next in line since you are new to RC flight, you will not likely be landing on a paved runway unless it is a huge paved parking lot. That means grass landings. That being said get larger tires. The new Apprentice 15e SAFe does have bigger tires than the original, but still not large enough for grass fields, especially if not closely mowed and smooth. The wheels will hang up on landing and take off causing the plane to nose over. Just 1 nose over on take off if you are not quick on the throttle will burn up the controller and motor. Wheels are cheap, motors and controllers are expensive. Nose over on landing can result in cart wheels tearing the Horz and Vert stabs off. Save your self that grief and get bigger wheels.

Next upgrade is a charger if you wish. The one supplied with the plane is just fine for the battery they supply. However if you get something like the Glazier I mentioned earlier, can be charged at a 5C rate vs 1C of the supplied charger. To get those 15 minute recharges wil require another charger. If you get a charger get a good one to grow with like a ICharger 1010B+. It will do anything you want with any battery.

Lastly the last upgrade I made was by necessity after a crash. I had to replace the ESC and motor. I also replaced the SAFE RX which caused the crash. So once you get familiar and confident with the plane I would upgrade to a 45 amp the ESC. This will give you a good performance boost. Just keep in mind if you replace the ESC make sure it has a minimum 5 amp BEC.

It is the BEC supplied with the plane which is number one suspect of the SAFE RX. It appears to be too small at 3 or 3.5 amps and browns out when the controller gets warm. When that happens it is twist and turn, crash and burn.

When it happened to me I replace the RX, a 60 AMP ESC, and 25 size motor. Plane performs beautifully. Hand launches great without throwing. Just hold it wings level, nose up, full power, and let go. Get to altitude, reduce power to 50% power, trim and fly for 20 worry free minutes.

Landing is easy, almost too easy if the CG is correct. If floats like a feather. If there is any wind above 5 to 7 mph, it lands like a helicopter, or even flying backwards with respect to ground. Me I quit doing that. I just cut the power, and push the nose down pointing just short of runway. Level off a couple of feet above ground, and let it set down with some speed. Otherwise it can float several hundred feet past you and run out of room.

Its a fun plane and with a few tweaks a great plane.

For your second plane, upgrade TX controller. The DX5 supplied with the Apprentice is extremely limited.
dereckbc is offline  
  Reply With Quote
Old 10-16-2013, 10:12 PM   #4
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

Originally Posted by xmech2k View Post
Hi Chris, and welcome to WF. You'll enjoy the Apprentice. I still have my original non-SAFE one, and enjoy flying it now and then.

As far as extra equipment, I'd just recommend an extra battery or 2. The stock charger is a little slow, but I find it best to charge at home the day before I go fly, and not bother with charging at the field. (Unless you're having a great LONG day at the field!) A better charger I think will save possibly 20 minutes on a charge, depending how far you run the battery down. To charge even faster things get a bit more complicated and would take a while to explain. To get started, a basic balancing 80w charger should serve you well for several years, unless you plan on moving on to bigger, higher power planes quickly. For a little more, there are nice 200w chargers available. I'd just recommend to be sure they are ones that you have to plug in the balance plug as well as the main connector so the charger can at least tell if you told it the right cell count. (I just watched a guy try to burn down his car recently this way.)

Here's some great reading material to learn about the batteries and such: Everything You Wanted to Know About Electric Powered Flight.

A box of rubber bands for the wings on the Apprentice is a good idea. The stock ones seem to deteriorate quickly. (They all deteriorate in the sun.) Use a all the included ones to secure the wing. I hear people who don't and experience the plane pulling up sharply in dives and other maneuvers because the front of the wings lift due to too few rubber bands. A spare prop or 2 is good to keep around so your flying doesn't get cut short by something that simple.

Just be sure to read the instructions and understand what SAFE can and cannot do. Out of curiosity, do you have any previous experience? Any aeronautical knowledge or simulator time? Or do you have someone who flies already and will help you get started? Some people can manage this right away, others take some time.

Good luck!


Hey,

Thanks for the quick great info, I would like to fly for 1-2 hours every Tuesday when I visit family. I know the stock battery will get 10 min of flight so it may look like I need to invest a good chunk of $ into batteries.

I have flown a few times but mainly stuck with RC Cars & Pico Helies, I did fly this exact plane before with some struggle. But that was because the owner never told me exactly what Beginner mode does. I was constantly fighting the plane from leveling out (because I didn't know it did that). But after watching and reading many things on this place it seems like SAFE does 75% of the flying for you on Beginner mode.

With that being said, I feel pretty safe flying alone with the on board "instructor".

I'll need to check out that link you posted, thanks again.
MKE-Flyer is offline  
  Reply With Quote
Old 10-16-2013, 10:18 PM   #5
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

Originally Posted by dereckbc View Post
I have an Apprentice 15e with SAFE. Be aware it is known to have some glitches which can cause loss of control.

The two things I highly recommend is as many battery packs as you can afford. I do not recommend buying any of the E-Flite batteries as they are expensive and low quality. Some very good ones are Glacier available from EP Buddy. I use both there 3S 2600 ($26) and 3S 3300 ($33). Both are about half the price of the E-Flite pack, have higher charge and discharge rates, and will last a lot longer.

Next in line since you are new to RC flight, you will not likely be landing on a paved runway unless it is a huge paved parking lot. That means grass landings. That being said get larger tires. The new Apprentice 15e SAFe does have bigger tires than the original, but still not large enough for grass fields, especially if not closely mowed and smooth. The wheels will hang up on landing and take off causing the plane to nose over. Just 1 nose over on take off if you are not quick on the throttle will burn up the controller and motor. Wheels are cheap, motors and controllers are expensive. Nose over on landing can result in cart wheels tearing the Horz and Vert stabs off. Save your self that grief and get bigger wheels.

Next upgrade is a charger if you wish. The one supplied with the plane is just fine for the battery they supply. However if you get something like the Glazier I mentioned earlier, can be charged at a 5C rate vs 1C of the supplied charger. To get those 15 minute recharges wil require another charger. If you get a charger get a good one to grow with like a ICharger 1010B+. It will do anything you want with any battery.

Lastly the last upgrade I made was by necessity after a crash. I had to replace the ESC and motor. I also replaced the SAFE RX which caused the crash. So once you get familiar and confident with the plane I would upgrade to a 45 amp the ESC. This will give you a good performance boost. Just keep in mind if you replace the ESC make sure it has a minimum 5 amp BEC.

It is the BEC supplied with the plane which is number one suspect of the SAFE RX. It appears to be too small at 3 or 3.5 amps and browns out when the controller gets warm. When that happens it is twist and turn, crash and burn.

When it happened to me I replace the RX, a 60 AMP ESC, and 25 size motor. Plane performs beautifully. Hand launches great without throwing. Just hold it wings level, nose up, full power, and let go. Get to altitude, reduce power to 50% power, trim and fly for 20 worry free minutes.

Landing is easy, almost too easy if the CG is correct. If floats like a feather. If there is any wind above 5 to 7 mph, it lands like a helicopter, or even flying backwards with respect to ground. Me I quit doing that. I just cut the power, and push the nose down pointing just short of runway. Level off a couple of feet above ground, and let it set down with some speed. Otherwise it can float several hundred feet past you and run out of room.

Its a fun plane and with a few tweaks a great plane.

For your second plane, upgrade TX controller. The DX5 supplied with the Apprentice is extremely limited.
Hey,

Thanks for the awesome info! I did read something about the wheels being too small for grass and causing the plane to flip. I'll look for some larger tires, most if not all of my landings will be on grass/soy fields.

The battery part is great, I will look into those batteries and purchase some ASAP. Do you know about how much extra time you got out of the different non OEM battery?

Thanks again!
MKE-Flyer is offline  
  Reply With Quote
Old 10-16-2013, 10:32 PM   #6
dereckbc
Member
 
Join Date: Jun 2013
Posts: 331
Thanked 6 Times in 6 Posts
iTrader: (0)
Friends: (3)
Default

Originally Posted by MKE-Flyer View Post
The battery part is great, I will look into those batteries and purchase some ASAP. Do you know about how much extra time you got out of the different non OEM battery?
On the supplied E-Flight 3300 pack about 15 to 20 minutes before it got to Low Voltage Cut Off when new and dropped pretty quickly after a dozen flights. Not sure who makes them but they are cheap.

The Glazier 2600 15 to 20 minutes initially before LVC and that is even after motor and ESC upgrade. After they get 10 to 15 flights will go up to 20 to 25 minutes. I fly at 50 to 60% power only going to full power at take off and loops, but only long enough to get up to altitude, or once I get to the top of a loop. On th e3300 packs, I just land after 20 minutes and still have to discharge to storage voltage.

You should be able to get the wheels at any local Hobby Shop. The Glazier batteries are only available from EP Buddy. The E-Flite battery has already dropped to 80% rated capacity and puffy. The Glazier are at 110% capacity and look good as new.

One tip I will give you on battery care is store them at the proper storage voltage 12.55 volts, place them in a zip lock bag with a couple of silica packs thrown in with them, and place in a warmer part of refrigerator like in a door compartment. I have a wine refrigerator which is perfect at 45 degrees. Just do not go below freezing and try to stay at 40 or above. Let them warm up in the zip lock bag before opening and let the silica pack do its job.
dereckbc is offline  
  Reply With Quote
Old 10-16-2013, 10:39 PM   #7
dereckbc
Member
 
Join Date: Jun 2013
Posts: 331
Thanked 6 Times in 6 Posts
iTrader: (0)
Friends: (3)
Default

Just another thought, it aint pretty but very effective. The plane is extremely easy to hand launch. If you have a rough grass feild you might consider taking the wheels off and belly land. I did this on another plane an Extra 300 and it works great. Just use either Duct or Box tape on the underside as a skid. YOu can even paint it Day Glow Orange or psychedelic puke purple which will greatly help you with orientation.

Hand launch at full power holding the PANIC BUTTON in beginner mode with a gentle toss into the wind
dereckbc is offline  
  Reply With Quote
Old 10-16-2013, 11:38 PM   #8
dahawk
Super Contributor
 
dahawk's Avatar
 
Join Date: Jul 2011
Location: Keller, TX
Posts: 3,387
View dahawk's Gallery6
Thanked 205 Times in 201 Posts
Club: 114th RC Aero Squadron
iTrader: (0)
Friends: (19)
Default

Welcome MKE,

Milwaukee ? I grew up there. Went to Marquette High School ('73). Denny( kyleservicetech) is also frrom the area and a big contributor here.

Another battery source that I've had a lot of luck with that you might try has been China Hobby Line(CHL) www.chinahobbyline.com They have the best prices, all they sell is batteries, free shipping from their California Warehouse. I'm very happy with them.

For chargers, I'm very happy with the Icharger 206B w/ 350W PS. . Progressiverc and EPbuddy sell them. If you plan on adding to the squadron, and you will once the addiction takes hold, you'll want something better than the cell phone chargers that come with the rtfs. But for now, you'll be fine. Some good deals out there.

Good luck with the new Apprentice S. I've been impressed with the ones I've seen showing up at the field. Appears that the Safe technology keeps them out of trouble.

Go Packers !

-Hawk
dahawk is offline  
  Reply With Quote
Old 10-17-2013, 12:56 AM   #9
xmech2k
Ya got any Beeman's?
 
xmech2k's Avatar
 
Join Date: Apr 2009
Location: San Diego, CA
Posts: 2,702
View xmech2k's Gallery21
Thanked 254 Times in 252 Posts
Club: CVMRCC, SEFSD
Awards Showcase

Scratchbuilders Award  1kW  Outstanding Contributor Award 
iTrader: (0)
Friends: (7)
Default

Dereckbc! You are doing all the wrong things to your batteries! The batteries need to be stored at ~50% capacity, which comes out to around 3.8 to 3.85v per cell. For a 3 cell, that's around 11.4 volts. You are storing them almost fully charged, which as I understand, builds the internal resistance of the cells, making them useless over time. I have only lost 2 batteries to bad performance. Both were accidentally flown to low voltage. One, and E-Flite batt that I flew to LVC once! The other, a Thunderpower I've had for almost 6 years, and got abused whiled training people with my Apprentice. It was run to LVC several times. The only other batteries I've had go bad were ones I dropped.

Also, you should avoid flying to low voltage cutoff, preferrably never doing it at all. For one thing, now you're putting your plane at risk as you have to land NOW. But it's bad for the batteries, too. I check my battery voltage after each flight(I check them before I fly, too! Make sure I have a full tank before takeoff!), and adjust my flight time to have about that storage voltage when the timer goes off. That way I have plenty of time for go-arounds if necessary, and my batteries have all lasted for years of continual use.

All this reminds me Chris, another good thing to buy right away is a battery voltage checker of any kind. There are the cheap ones that just plug into the balance plug. Get one that can tell you individual cell voltages, as it helps to see the health of the battery. You may want to get a device that can do that, and also be a wattmeter, so you can make sure you are not overtaxing your system later when you get into trying different props, motors, etc.

Cold storage isn't a bad thing. I've heard it's good for long term storage, but I think more importantly is keeping them from excessive heat. I understand the batteries don't perform well when cold, so at least I wouldn't fly them until they warmed up.
xmech2k is offline  
  Reply With Quote
Old 10-17-2013, 01:14 AM   #10
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

Hey everyone!!

I did go flying today!!! I flew my buddies plane and landed in 50F / slight drizzle w/ 10mph winds. I took off and landed alone without any problems.

Thanks for all the help, and yes I'm from Milwaukee. Go Pack Go!! Oh and go Brew Crew!

So I get my plane tomorrow for 284.99 + Tax and I plan to get a few extra batteries, props, wheels, battery checker & charger. I will post prices below and please let me know if you feel it's good (for local hobby shop).

Battery: 38.00
http://www.buddyrc.com/glacier-30c-3300mah-3s1p.html

Checker: 25.00
http://www.buddyrc.com/battery-volta...y-checker.html

Charger: 62.00
http://hitecrcd.com/products/charger...harger/product

Thoughts?
MKE-Flyer is offline  
  Reply With Quote
Old 10-17-2013, 01:45 AM   #11
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

Well I was going to get the iCharger 1010B+ but the power supply for home charging is $123.00, I just want to charge 2 batteries at once.

The charger I posted above is only 6 Amps and cant fully charge the batteries (assuming).

Any ideas?
MKE-Flyer is offline  
  Reply With Quote
Old 10-17-2013, 01:49 AM   #12
xmech2k
Ya got any Beeman's?
 
xmech2k's Avatar
 
Join Date: Apr 2009
Location: San Diego, CA
Posts: 2,702
View xmech2k's Gallery21
Thanked 254 Times in 252 Posts
Club: CVMRCC, SEFSD
Awards Showcase

Scratchbuilders Award  1kW  Outstanding Contributor Award 
iTrader: (0)
Friends: (7)
Default

Those things look fine.

On the battery, if you're looking for longer flight times, you need more mAh. But along with more mAh comes more size and weight. So it's a balancing act. You'll be able to fly longer, but will it effect the center of gravity, and how will the plane handle the extra weight? Of course that's if it fits... I think you'll find 10 minute flight times are pretty good. And I see those batteries say they have a 5C charge rate? It's recommended to still only charge at 1C for the first 5 flights or so to 'break them in'. Even then, I would only charge them at faster than 1C if I just HAD to fly RIGHT NOW! It is harder on the batteries.

And of course, there's the wattage of the charger to consider. At only 50 watts, it will just handle 1C charge rate.Yes, it says it can charge a 6 amps, but the wattage limits it as well. Fully charged, a 3 cell battery is at 12.6v.(4.2v per cell) And 1C charge rate is 3.3 amps for a 3300mAh battery. So 12.6v*3.3A=41.58w. It will work OK, but you don't have much room for growth. Of course, many planes out there use smaller batteries, so if you don't plan on going to bigger planes or EDF's with 4+cells, it could work for you. One nice thing about that charger is the AC/DC capabilities. No power supply to mess with.

As far as the tires, it looks like the Apprentice S already has larger tires and taller landing gear than its predecessor. They listened to the problems people had with the original. Your problem may already be solved.
xmech2k is offline  
  Reply With Quote
Old 10-17-2013, 01:52 AM   #13
xmech2k
Ya got any Beeman's?
 
xmech2k's Avatar
 
Join Date: Apr 2009
Location: San Diego, CA
Posts: 2,702
View xmech2k's Gallery21
Thanked 254 Times in 252 Posts
Club: CVMRCC, SEFSD
Awards Showcase

Scratchbuilders Award  1kW  Outstanding Contributor Award 
iTrader: (0)
Friends: (7)
Default

You posted again while I was typing! I don't understand what you mean about not being able to fully charge the batts with that charger?

You may look around on Craigslist or somewhere for a power supply. I picked up a 30A one for $20.
xmech2k is offline  
  Reply With Quote
Old 10-17-2013, 01:54 AM   #14
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default New Apprentice 15e, what accessories?

The batteries are 3.3a and the charger only does 6A, won't that cause any issues?
MKE-Flyer is offline  
  Reply With Quote
Old 10-17-2013, 01:57 AM   #15
rcers
Community Moderator
 
rcers's Avatar
 
Join Date: Jul 2005
Location: Trophy Club TX
Posts: 6,201
View rcers's Gallery57
Thanked 502 Times in 492 Posts
Awards Showcase

WAA-08 Pilot 
iTrader: (4)
Friends: (9)
Default

The charger is adjustable and will do anything from .1 amp to 6 amps. So you set yours to 3.3 Amps and 3s and you are good to go. It will be a great charger for you don't worry too much about the 50w limit for now.

Mike
rcers is offline  
  Reply With Quote
Old 10-17-2013, 02:25 AM   #16
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default New Apprentice 15e, what accessories?

Oh, cool!

My buddy has that charger and he does two at once and says there are issues charging them at the same time. But he's also new to the hobby, maybe all is well.

I feel very stupid asking basic questions, I'm in the saltwater hobby and I know how hard it is answering basic questions. But it really means a lot when you all do.
MKE-Flyer is offline  
  Reply With Quote
Old 10-17-2013, 02:37 AM   #17
rcers
Community Moderator
 
rcers's Avatar
 
Join Date: Jul 2005
Location: Trophy Club TX
Posts: 6,201
View rcers's Gallery57
Thanked 502 Times in 492 Posts
Awards Showcase

WAA-08 Pilot 
iTrader: (4)
Friends: (9)
Default

Originally Posted by MKE-Flyer View Post
Oh, cool!

My buddy has that charger and he does two at once and says there are issues charging them at the same time. But he's also new to the hobby, maybe all is well.

I feel very stupid asking basic questions, I'm in the saltwater hobby and I know how hard it is answering basic questions. But it really means a lot when you all do.
Just stick with one at a time for now.

Ask away - we all asked these questions when we stated too.
rcers is offline  
  Reply With Quote
Old 10-17-2013, 03:20 AM   #18
dereckbc
Member
 
Join Date: Jun 2013
Posts: 331
Thanked 6 Times in 6 Posts
iTrader: (0)
Friends: (3)
Default

Originally Posted by xmech2k View Post
Dereckbc! You are doing all the wrong things to your batteries! The batteries need to be stored at ~50% capacity, which comes out to around 3.8 to 3.85v per cell.
No Sir just fat fingers on the key board. I said 12 .55 volts which is near 100%. 11.55 volts is what I fat fingered should have been said. My bad.

Temperature, humidity, and storage I stand by. Thanks for pointing out my Fat Finger error.
dereckbc is offline  
  Reply With Quote
Old 10-17-2013, 03:47 AM   #19
dereckbc
Member
 
Join Date: Jun 2013
Posts: 331
Thanked 6 Times in 6 Posts
iTrader: (0)
Friends: (3)
Default

Originally Posted by MKE-Flyer View Post
The batteries are 3.3a and the charger only does 6A, won't that cause any issues?
No Sir. If the batteries are 3.3 AH aka 3300 mah and you have a charger/PS that can deliver up to 6 amps means the charger can charge up a 3.3 Amp Hours /6 Amps = .55 hours or just over 30 minutes from fully discharged to fully charged in just about 30 minutes.

If memory serves me correctly the Apprentice comes with a 2 amp charger for 3S batteries. So if you had your 3.3 AH battery fully discharged it would take on paper your charger 3.3 AH / 2 A = 1.65 hours to fully recharge the battery.

So it is simple math of Hours = Amp Hours / Amps. From that formula we can also say Amps = Amp Hours / Hours.

OK to apply that idea we need to match our charger and power supply to work with each other. General rule for compatibility is the DC Power Supply Watts need to be equal or greater than the charger capacity. So if we have a charger than charge at say 300 watts, needs a power supply at 300 watts or greater.

So for example lets say you have a 3S 3 AH battery pack you want to charge at 5C where C = Battery Amp Hour Capacity. 5C = 3 amps x 5 = 15 amps. To do that would require a power supply can supply 15 amps x 13 volts = 195 watts.

How to apply all this math mumbo jumbo is make sure your power supply equals or exceeds your charger requirements.

So if you were to buy say a ICharger 1010B+ you need a minimum 300 watt 13.5 volt power supply to take full advantage of the charger. With a 3S battery pack can supply up to 23 amps charge current. Or on a 3S 3 AH battery a C/.13 charge rate or less than 15 minutes if such a battery existed that can take that high of a charge rate.
dereckbc is offline  
  Reply With Quote
Old 10-17-2013, 03:53 AM   #20
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

Originally Posted by dereckbc View Post
No Sir. If the batteries are 3.3 AH aka 3300 mah and you have a charger/PS that can deliver up to 6 amps means the charger can charge up a 3.3 Amp Hours /6 Amps = .55 hours or just over 30 minutes from fully discharged to fully charged in just about 30 minutes.

If memory serves me correctly the Apprentice comes with a 2 amp charger for 3S batteries. So if you had your 3.3 AH battery fully discharged it would take on paper your charger 3.3 AH / 2 A = 1.65 hours to fully recharge the battery.

So it is simple math of Hours = Amp Hours / Amps. From that formula we can also say Amps = Amp Hours / Hours.

OK to apply that idea we need to match our charger and power supply to work with each other. General rule for compatibility is the DC Power Supply Watts need to be equal or greater than the charger capacity. So if we have a charger than charge at say 300 watts, needs a power supply at 300 watts or greater.

So for example lets say you have a 3S 3 AH battery pack you want to charge at 5C where C = Battery Amp Hour Capacity. 5C = 3 amps x 5 = 15 amps. To do that would require a power supply can supply 15 amps x 13 volts = 195 watts.

How to apply all this math mumbo jumbo is make sure your power supply equals or exceeds your charger requirements.

So if you were to buy say a ICharger 1010B+ you need a minimum 300 watt 13.5 volt power supply to take full advantage of the charger. With a 3S battery pack can supply up to 23 amps charge current. Or on a 3S 3 AH battery a C/.13 charge rate or less than 15 minutes if such a battery existed that can take that high of a charge rate.
So with this charger http://hitecrcd.com/products/charger...harger/product , and the ParaBoard I can charge two S3 batteries at once?

If I can get away with this charger and two batteries at once I'm a happy flyer.
MKE-Flyer is offline  
  Reply With Quote
Old 10-17-2013, 04:05 AM   #21
dereckbc
Member
 
Join Date: Jun 2013
Posts: 331
Thanked 6 Times in 6 Posts
iTrader: (0)
Friends: (3)
Default

[QUOTE=MKE-Flyer;927246]So with this charger http://hitecrcd.com/products/charger...harger/product , and the added expansion board I can charge two S3 batteries at once? Yes and No. It is a 50 watt charger. A 3S battery is 12.6 volts. 50 watts / 12.6 volts = 3.96 amps. Lets just 4 amps.

So yu could charge say a single battery at 4 amps, 2 batteries at 2 amps, 3 batteries at 1.3 amps. What that effects is the time it takes to charge up.

If you are looking for an upgraded charger to last you a while as you progress look for something like a 200 watt charger. That will charge up your Apprentice 3300 mah battery if fully discharged with 15 amps or less than 15 minutes. Or 2 batteries in 30 minutes, 4 batteries in 1 hour. Remember AH, A and H are directly proportional to each other like an hourly wage.

If you need to earn $400 and make $5/hr; how many hours do you have to work?
dereckbc is offline  
  Reply With Quote
Old 10-17-2013, 04:08 AM   #22
MKE-Flyer
Member
 
Join Date: Oct 2013
Posts: 68
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

[QUOTE=dereckbc;927247]
Originally Posted by MKE-Flyer View Post
So with this charger http://hitecrcd.com/products/charger...harger/product , and the added expansion board I can charge two S3 batteries at once? Yes and No. It is a 50 watt charger. A 3S battery is 12.6 volts. 50 watts / 12.6 volts = 3.96 amps. Lets just 4 amps.

So yu could charge say a single battery at 4 amps, 2 batteries at 2 amps, 3 batteries at 1.3 amps. What that effects is the time it takes to charge up.

If you are looking for an upgraded charger to last you a while as you progress look for something like a 200 watt charger. That will charge up your Apprentice 3300 mah battery if fully discharged with 15 amps or less than 15 minutes. Or 2 batteries in 30 minutes, 4 batteries in 1 hour. Remember AH, A and H are directly proportional to each other like an hourly wage.

If you need to earn $400 and make $5/hr; how many hours do you have to work?

Awesome info!! Thanks!

Now to answer your math question.... It all depends on your tax rate..
MKE-Flyer is offline  
  Reply With Quote
Old 10-17-2013, 04:09 AM   #23
dereckbc
Member
 
Join Date: Jun 2013
Posts: 331
Thanked 6 Times in 6 Posts
iTrader: (0)
Friends: (3)
Default

With Batteries the general formulas are:

Amp Hours = Amps x Hours
Amps = Amp Hours / Hours
Hours = Amp Hours / Amps
dereckbc is offline  
  Reply With Quote
Old 10-17-2013, 04:11 AM   #24
dereckbc
Member
 
Join Date: Jun 2013
Posts: 331
Thanked 6 Times in 6 Posts
iTrader: (0)
Friends: (3)
Default

[QUOTE=MKE-Flyer;927248]
Originally Posted by dereckbc View Post


Awesome info!! Thanks!

Now to answer your math question.... It all depends on your tax rate..
With batteries we call that Peukert Law. Fortunately with Lipo that tax rate is very low around 1 to 2 % so we can ignore it. With Lead Acid around 20%.
dereckbc is offline  
  Reply With Quote
Old 10-17-2013, 04:12 AM   #25
xmech2k
Ya got any Beeman's?
 
xmech2k's Avatar
 
Join Date: Apr 2009
Location: San Diego, CA
Posts: 2,702
View xmech2k's Gallery21
Thanked 254 Times in 252 Posts
Club: CVMRCC, SEFSD
Awards Showcase

Scratchbuilders Award  1kW  Outstanding Contributor Award 
iTrader: (0)
Friends: (7)
Default

LOL the fat finger thing! Glad it's not the case. And I guess I shouldn't have said you're doing everything wrong with your batteries. The temperature thing isn't anything that will damage them, and I guess could help keep them longer.

What about flying repeatedly to LVC? That could be the reason your batts didn't last so long.

As far as charging times, it isn't always as easy as that math. The cell voltages increase with the charge state. Also, the charger ramps up fairly quickly to the desired charging amps, but at the end of the charge cycle the current gets lower and lower to pack the final electrons in. Something about if it quit right when it hit 4.2v, the voltages would bounce back down. Or it's not good to run right up to 4.2v at the full amps. I'm not an expert, but that's what Iread from someone who is. So it takes quite a bit longer than what the math says. My guess would be to add around 10 minutes to the calculations.

Also, the charger Chris linked won't be able to charge a 3 cell at 6 amps, since it's limited to 50 amps. 12.6v * 6A = 75.6w If it's smart enough, it might limit the amps, or else the magic smoke might be released.
xmech2k is offline  
  Reply With Quote
Reply

  WattFlyer RC Electric Flight Forums - Discuss radio control eflight > Electric R/C Airplanes > Beginners

« Previous Thread | Next Thread »

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Apprentice S 15e ESC Programming Mode dereckbc General Electric Discussions 4 07-21-2013 12:13 AM
Apprentice 15e equivalent in Phoenix? MX5Seeker Flight Simulators 4 08-10-2012 09:01 PM
Need Apprentice 15E Motor paxskipper Beginners 8 04-13-2012 09:00 PM
Help with my Apprentice 15e motor BlinkguY Power Systems 2 12-10-2011 12:57 AM
Increasing wheel size on Apprentice 15e - axle size? kleecker ParkFlyers 19 04-04-2011 02:24 PM


All times are GMT +1. The time now is 10:28 AM.


Powered by: vBulletin
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 WattfFlyer.com
RCU Eflight HQ

Charities we support Select: Yorkie Rescue  ::  Crohn's & Colitis Foundation



Page generated in 0.31062 seconds with 67 queries