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fmelindy
06/18/2010, 03:27 PM
Is it possible to adapt any old float switch you have lying around for use with the Aquatronica controller by just attaching the appropriate connector and plugging it in?

landy
06/18/2010, 07:27 PM
Nope, you will need to add a few resistors. I think there is a thread around here that has some info.

fmelindy
06/23/2010, 06:55 PM
Wouldn't happen to have a link to further info, would you? I can't seem to find anything on all my browsing and searching.

RobbyG
07/01/2010, 03:04 PM
I posted it years ago, but Reefcentral has lost hundreds of thousands of posts when they changed software. I can't remember what the values were but there were two resistors. UInfortunetly I don't have a spare one cut open again to find out again.
Sorry.

landy
07/01/2010, 09:58 PM
Ok, just too lazy to get the meter out of my truck,

Mine reads:
Low = 296 Ohms +-
High = 468 +-

So for this to work, the switch must be normally closed with a 468 Ohm +- resistor across. And an 800 ohm +- resistor connected switch side.

Basically, if the water level is low the switch is closed placing the resistors in parallel. If the water is high, the switch opens and the 468 +- is all alone.

Landy

fmelindy
07/03/2010, 06:51 PM
Thanks for the info. I hate to sound like a moron, but how would one wire this together?

landy
07/04/2010, 01:37 AM
http://www.reefcentral.com/forums/picture.php?albumid=1811&pictureid=17586

sorry, hope this will make more sense.

landy

fmelindy
07/04/2010, 08:47 PM
yes, that's perfect actually. So what's the worst case scenario if this is tried and fails? Could it somehow destroy my controller? (unlikely, I know)

landy
07/04/2010, 09:39 PM
yes, that's perfect actually. So what's the worst case scenario if this is tried and fails? Could it somehow destroy my controller? (unlikely, I know)

worse case, when you plug it in, the earth will implode...:eek2:

Iím not sure how sensitive the controller is to the resistance values, if they are wrong, it just wonít work, or the controller with recognize it as something completely different.

landy

fmelindy
07/05/2010, 04:51 PM
Yes, I was really concerned about the implosion... I don't want to be the one who makes all those post-apocalyptic movies out to be prophecy!

RobbyG
07/09/2010, 01:02 PM
If the 468 ohm is off by to much the AQT may think it's another device and not a float sensor, if it's resistance is too low it may draw to much current and damage the interface (Unlikely). BTW it's easy to get the correct values, try RatShack.