algutkin
Posts: 580
Score: 100
Joined: 8/7/2003
Last Login: 3/10/2010
From: Orange,
CA, USA
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Dalton:
Here is algutkins layman's explanation of what goes with what. A complete layman's point of view, wrong forum, but, what the heck.
The only difference between the motors seems to be minor. I did several conversions and used Axi motors in the same category but different /?? numbers. They all worked fine. If you look at the Hobby Lobby web site and compare the motors in the same category you will see that the differences don't appy to the Telemaster situation. It seems that the differences are primarily the ability to accept more volts. More volts are achieved with more cells in series. With more volts, you get more RPM. The motors are rated at both RPM per volt and amps that they can withstand before burning out. With the Senior Telemaster, RPM doesn't matter, it's the amp draw, which involves batteries in parallel. The more batteries in parallel, the more duration of flight, and the ability to take the amp draw of the 4100 or 4300 motor.
This comparison seems complicated at first, because we are not electrical engineers. To me the first question is, how many RPMs are needed to achieve the desired specs of the airplane? After all we are trying to emulate the nitro version. OK, lets say the specs call for X sized prop at X RPMs. The motor is rated for X RPMs per volt, and the prop sizes are also listed, so that tells us that 11.1 volts from a 3S lipo is enought to run the motor at X RPM with suggested prop size. Next, if you have a 1200mah pack of batteries in 3S configuration, that will work because it will produce 11.1 volts, however, the motor will run a very short time and the batteries will get hot. So next, the amp draw has to be calculated. If you don't want to calculate amp draw, just keep adding 3S battery packs in parallel until the batteries don't get hot. Batteries in parallel determine available amps. So, if you detmine that amp draw is 32amp, then you need batteries that can withstand that kind of draw. A normal inexpensive pack, at 8C is able to withstand 8 amps, It think. So you need 4 1200mah 3S packs in parallel in order to satisfy the volt and amp requirement. That means, 11.1 volts, 4800mah, at 32 amp draw.
Disclaimer:
I had two glasses of wine during lunch today, so.......There will probably be some posts after mine that dispute and or clarify the layman's view that I have expressed. However, this crazy method has worked for me just fine. I run up the motors, check the amps, check the battery temps, check the controller temp, and add batteries in parallel if the batteries are warm. If the controller is warm, I just add a more powerfull controller. My method is not perfect, there are others that use calculation programs to get in the ball park, then they modify everything after while twinking up the configuration. The cost to them is not any less than the cost using my method, whatever works. My planes fly just fine, it's the pilot that is the problem.
Summary:
Do it, see what happens. The Telemaster will fly with an electric band powered propeller. Fly the thing and don't worry.
Al
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All Forums >> Electric Aircraft Universe >> Glow to Electric Conversions >> RE: Hobby Lobby Sr. Telemaster ARF 
RE: Hobby Lobby Sr. Telemaster ARF - 
