Quote:
Originally Posted by macafee2
How does the sun blind of a saloon detect it is all the way up or down? ... how does the blind know, it's down and does not try to go down and therefore break?
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That's a very intelligent question Ian. RAVE has the explanation:
"... the sun blind switch contains ... a controller circuit, a Field Effect Transistor (FET) and a current monitor. Each time the switch is pushed, the controller circuit modulates the FET for a timed period to produce the power outputs to the motor and gearbox. The current monitor limits the current draw of the outputs to the motor and gearbox."
You don't have to be an electronics wizard to get the gist of that. The timed period is 2.5 ± 0.1 seconds. The maximum current draw is 3.2 ± 0.1 amps for 500 ± 20 mS.
See how much technology and effort goes into the design of a toy.
Simon