[NSRCA-discussion] Electric Power Consumption

[Dean Pappas]

Hi George,
The answer is less prop, but as Adam said, if you have fried the magnets in the motor with the overcurrent running you've gone through, then the motor will pull excessive current on any useful prop.
Dean

	-----Original Message----- 
	From: nsrca-discussion-bounces at lists.nsrca.org on behalf of George Miller 
	Sent: Tue 1/10/2006 10:20 PM 
	To: discussion at nsrca.org 
	Cc: 
	Subject: [NSRCA-discussion] Electric Power Consumption
	
	
	I have a problem with an electric conversion which while not precisely pattern related, I'm sure will be applicable to electric pattern problems...so I'll ask it here.
	 
	I am trying to convert a Showtime from YS 110 4 cycle power to electric power.  After looking around the web, I got an Actro 32-3 - which is a popular motor for the Ion electric helicopter.  I know that this motor runs well with available ESC's on 5S4P lithium packs, so I set it up with a 17X12 APC e prop and a 77amp ESC from Hobby Lobby  ( esc and prop recommended on their website).    To make a long story short, the ESC litterally burned up 30 seconds into the first flight....but BOY WHAT POWER for that 30 seconds<G>!!!
	 
	OK, so I'm thinking that burning up probably indicates a problem.....and I start to investigate...I hook up a watts-up to my Focus II with a Plettenberg 30-10 and a 21X12 APC and it pulls about 65 amps at full throttle on the bench....Then I set up the Showtime and it tops 75 amps at half throttle!! HMMM, so there is the problem....Now I try to make changes to decrease the amperage -- larger prop and smaller prop---no major change, then I tried just using a 5 cell pack cutting voltage in half...still about the same....so the question is:  How do you adjust the current drawn by an electric motor?  Can this set up be salvaged...Where did I go wrong and how can I avoid this in the future? 
	 
	TIA for your help and the benefit of your experience!
	 
	George

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