Quote:
Originally Posted by macafee2
..sorry still don't understand ..
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OK, no problem Ian.
The sun blind switch contains a sophisticated electronic circuit. When you push the button to raise your sun blind, this circuit sends a voltage to the motor. The motor then runs and raises the blind.
You asked how the blind knows that it is "all the way up or down". The answer is that it doesn't. The movement of the blind is stopped by the voltage being removed from the motor after it has run for two and a half seconds. It has been calaculated that this is the exact time required for the motor to drive the blind up or down. The voltage to the motor is switched on and off by the electronic circuit in the sun blind button. That's the answer to your later question: "what stops it?".
That's basically how it works. There's a safety mechanism to prevent the motor burning out if something goes wrong and that's the "current monitor". Please say so if you want to know more about that.
Is that any clearer? If not, it's no problem, just let me know which bits are confusing and I'll think of another way to explain it.
Simon
