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Old 07-15-2007, 01:35 AM   #1
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Default Brushless problem any help welcome....

Hi i went to run my associated tc5 today with a 4.5 gm motor with lrp tc spec speedy the car ran very very well but when i went to do starts they car darted off the line stopping and starting then veering to the right.... has any one got any solutions?......]
cheers russell.....
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Old 07-15-2007, 11:25 AM   #2
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Sounds like you have a voltage drop problem. When you get on the throttle off the line, the motor draws a ton of power and the main pack voltage drops. If it drop far enough down the radio will not get enough voltage to run. I had a similar problem and I added a couple of caps to the receiver to help if ride through the voltage drop. Here is a pic. the big cap is 4700uF and the little cap is 0.1uF (brushed motor size). This helped my problem. I diagnosed the problem by using a receiver pack for a run. Make sure you pull the red wire out of the ESC plug before you use a receiver pack. When my car worked better with the receiver pack I figured that the BEC voltage was to blame and the caps helped smooth things out. The big cap powers the receiver during voltage dips and the little cap filters out higher frequency noise.
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Old 07-15-2007, 12:19 PM   #3
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Quote:
Originally Posted by kufman View Post
Sounds like you have a voltage drop problem. When you get on the throttle off the line, the motor draws a ton of power and the main pack voltage drops. If it drop far enough down the radio will not get enough voltage to run. I had a similar problem and I added a couple of caps to the receiver to help if ride through the voltage drop. Here is a pic. the big cap is 4700uF and the little cap is 0.1uF (brushed motor size). This helped my problem. I diagnosed the problem by using a receiver pack for a run. Make sure you pull the red wire out of the ESC plug before you use a receiver pack. When my car worked better with the receiver pack I figured that the BEC voltage was to blame and the caps helped smooth things out. The big cap powers the receiver during voltage dips and the little cap filters out higher frequency noise.
Agreed, sounds like the receiver not getting enough voltage from the BEC to run properly(which can happen under extreme amp draw situations, & that sounds like what aussie racer's experiencing). Try the big cap on your receiver & see if that fixes it(it should at least help a little, if not fix it entirely, oh, & Spektrum & Novak both sell those caps already wired with a plug you can just connect right into the receiver straight away, no muss, no fuss).....
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Old 07-16-2007, 03:21 AM   #4
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Well thanks for all the opions and emails i have found one problem that tony porter from harrisrc in australia pointed out is the speedy in mode 1 is still on the auto battery feature am going to try tonight at track with the 4-7 cell nimh setting and if not going to try some caps i have.... will let know what happened.....
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