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HX3D014
12-02-2006, 04:37 AM
3 things
Voltage
Amperage
resistance

Step up Voltage
increase winde

So 10v at 10A = 100Watt

Resistance is inbuilt into everything, Even batteries

a motor with 5 pols and 20 windes ea, on 10vbat and 10A curent draw
is still 100watt

so what do windings change (Push?,RPM, Torque,)..Resistance of electron flow, and therefor more power dicipation.
what do we need to concider if we increase a few winds.
Provided we have an ESC that can handle the current and Higher rpm AC, and a battery that can do likewise with the power Amps. then the last thing would be the Conduit itself, the wire? So my Question would be

Dose the wire have to be able to handle higher voltage if i have not increased the bat voltage. just the number of winds ? lets say i know it is able to handle more amps, but how do i know how to do the math on it.
is there a formula ?

B.L.E.
12-02-2006, 05:24 AM
Changing the number of turns changes the motor's kv. Take a motor that draws 10 amps at 10 volts for 100 watts of power. Now double the turns of the winding and it will still be a 100 watt motor, only now it will draw 5 amps at 20 volts to make that power.

HX3D014
12-14-2006, 09:46 AM
Changing the number of turns changes the motor's kv. Take a motor that draws 10 amps at 10 volts for 100 watts of power. Now double the turns of the winding and it will still be a 100 watt motor, only now it will draw 5 amps at 20 volts to make that power.
Changing the number of turns changes the Motors KV. Corect.
double the turns and it could still be a 100 watt motor. Corect.
Double the turns. need to half the thickness of Coil wire. that will mean the wire is now only able to handel a maximum ???? Amp or volt. this i dont know.

now it will draw 5 amps at 20 volts to make that power. Wrong. well could be corect. but you may need to change ESC and bat pack. more like.

double the wind and double the resistance. there for load there for Amp.

I am not sure if corect on double wind will exact double resistance there for exact double amps

stroland
12-14-2006, 09:52 PM
im still kinda new at winding motors but i can tell you ohms law, if r or resistance gos up then i or current gos down now as v or voltage gos up current gos up too. all so in a coil as the number of turns go up so doses r allso as frequicy gos up so dose r. allso as r gos up THE VOLTAGE DROP across the coil will go up. hope that helps you some

B.L.E.
12-15-2006, 01:46 AM
Changing the number of turns changes the Motors KV. Corect.
double the turns and it could still be a 100 watt motor. Corect.
Double the turns. need to half the thickness of Coil wire. that will mean the wire is now only able to handel a maximum ???? Amp or volt. this i dont know.

now it will draw 5 amps at 20 volts to make that power. Wrong. well could be corect. but you may need to change ESC and bat pack. more like.

double the wind and double the resistance. there for load there for Amp.

I am not sure if corect on double wind will exact double resistance there for exact double amps


Actually, doubling the turns and cutting wire area in half will quadruple the motors's winding resistance. Not only is the conductor twice as long (doubling the resistance) but it also has only 1/2 the cross sectional area (doubling the resistance again). Power losses from I^2 X R will be the same however.
Some single phase induction motors are wound with two conductors. Each conductor is treated as a separate circuit. Hooked up in parallel and the motor runs on low voltage (115 volts), hooked up in series and the motor runs on high voltage (230 volts). In either mode, the motor has the same power and efficiency.

ron_van_sommeren
12-20-2006, 05:32 PM
Brian Mulder's must read motor building articles, will prevent you from asking a lot of questions ;)
www.southernsoaringclub.org.za (http://www.southernsoaringclub.org.za/)
-> articles from Southeasters
-> electric motors, part 1-5

Do-it-yourself motor homepages, manuals/tutorials, checks and tests in the first message of this motor builders tips and tricks thread. The checks and tests may save you from frying your controller or motor. Thread is active, bookmark it for future reference and subscribe to it:
http://www.rcgroups.com/forums/showthread.php?t=240993 (sticky thread, at top of subforum)

Ralph Okon's motorbuilder bible:
www.powercroco.de (http://www.powercroco.de)
Don't let the German language deter you, a picture(s) is worth a thousand words, and you can use an online translation tool, e.g. http://babelfish.altavista.com

Vriendelijke groeten ;) Ron
diy brushless motor discussion group (http://www.yahoogroups.com/group/lrk-torquemax)
Drive Calculator (http://www.yahoogroups.com/group/D-calc/) download & discussion group
int. E fly-in & diy outrunner meet (http://home.hetnet.nl/%7Eronvans/), Aug.26 2007, Nijmegen, the Netherlands

HX3D014
12-21-2006, 10:39 PM
Thank you.


WOW

ron_van_sommeren
12-22-2006, 12:31 PM
Forget about wire resistance (for now), it only effects rpm drop under load, a motor is not a simple resistor. Wire resistance does effect efficiency though. Always use the thickest wire possible for a given number of winds, or wind two-three in parallel (still counts as one wind).

Vriendelijke groeten ;) Ron
diy motor building tips & tricks (http://www.rcgroups.com/forums/showthread.php?t=240993)
diy brushless motor discussion group (http://www.yahoogroups.com/group/lrk-torquemax)
Drive Calculator (http://www.yahoogroups.com/group/D-calc/) download & discussion group
int. E fly-in & diy outrunner meet (http://home.hetnet.nl/%7Eronvans/), Aug.26 2007, Nijmegen, the Netherlands

HX3D014
12-22-2006, 08:19 PM
can you post here for me;

some formulas including all short hand
basic description of ea
I'm Looking for
1st (Ones i have since forgot)
2nd Any other's relative to Burshless motors.
At least VIR. Resistance paralel = new resistance
and capacitance series paralel (Not sure if relavant to Elec motors),
I'm thinking the capacitance of magnet and capacitance of wound wire. Or would this be just like priming a gas engin.
Thanks in advance. (Mean time I am reading the info you sent and will) see if the answers are there. So far i have learnt at least 10 new things)
Enough to know i Need not edit the above) but enough to answer for my self the above. but not enough to conficently post an essay on. (Give me a week Or two. sir!)
Bryce Ring

Mean time Who would be confident enough to specualate on the capability and changes require (IF) to get this motor (http://www.modelmotors.cz/index.php?page=61&product=5330D&serie=20&line=GOLD)to 3D this Aircraft (http://www.hangar-9.com/Products/TechnicalSpecs.aspx?ProdID=HAN1100).