Re: Sensing my garage door

["Frank Mc Alinden" <armagh@xxxxxxx>]

Hi Paul


> Two lines for the open/close operation - simple!

I take it these are command signals from Homevision ..is that correct ? and
is the logic normally low go high (+5V) or high  go low.......

I will do a schematic and get it off to you on the above assumption

Frank

----- Original Message -----
From: "Paul" <p-gale@xxxxxxx>
To: <ukha_d@xxxxxxx>
Cc: "Frank Mc Alinden" <armagh@xxxxxxx>
Sent: Saturday, April 05, 2003 7:30 PM
Subject: [ukha_d] Sensing my garage door


> One for the electronics experts:
>
>
>
> In an attempt to remotely control and sense the condition of my garage
> door, I've run several signals back from my garage door opener as
> follows:
>
>
>
> Two lines for the open/close operation - simple!
>
> Three lines taken from the position micro switches - Gnd, +5V when
open,
> +5V when closed.
>
>
>
> I'm trying to feed the microswitch signals into an opto-isolated
simple
> circuit and then into HomeVision so that I can tell when the door is
> open/closed. The trouble is, I don't want to affect the garage door
> opener in any way (and break it!).
>
>
>
> I've currently got one of the gnd and +5V signals fed into the input
of
> the opto with a 1K resistor in series. Is this enough? How can I
> maintain the +5V potential of the garage door circuit (and effectively
> not effect it) but at the same time sense the voltage (very high value
> resistor instead of the 1K???). Does that make sense?
>
>
>
> If anyone can help (Frank?), I can sketch the setup if my explanation
is
> not clear.
>
>
>
> TIA  :-)
>
>
>
> Paul.
>
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> UKHA2003 BE THERE! Details here:
http://www.automatedhome.co.uk/article.php?story_id=1110
> http://www.automatedhome.co.uk
> Post message: ukha_d@xxxxxxx
> Subscribe:  ukha_d-subscribe@xxxxxxx
> Unsubscribe:  ukha_d-unsubscribe@xxxxxxx
> List owner:  ukha_d-owner@xxxxxxx
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>