Re: Automatic Up/Down Window Module

[Huw Powell <human@nh.ultranet.com>]

> Hmmm- Lets see, when a DC motor stops turning there is no back emf, so the
> current is only limited by the circuit resistance (low). The large current
> will be flowing through the brushes and armature of the motor. Sooo we get the
> convenience of auto up/down at the expense of a burned up motor. Not a good
> trade. But wait-- Audi engineers would not design power windows without an end
> of travel interrupt switch,would they??. 

of course they would.  but, the failure mode on these things is the
cable snapping or jamming, not the motor burning out, right?  Though I
wonder if at wire replacement time, one should try to replace the
brushes and clean the armature?  Oh boy.

-- 
Huw Powell

http://www.thebook.com/human-speakers

82 Audi Coupe; 85 Coupe GT
http://www.nh.ultranet.com/~human