ATO problem

[chipmaker]

I put my own ATO system together. Typical ato with relay, (2) float switches, and pump. What my problem is, is when the water level is at the point where its about ready to shut off, the relay just sets there and chatters. With the chattering (contacts opening and closing rapidly) its enough to break the pumps power, and keeps the pump from adding any more water. I am using an MiniJet (404 or a 606) for pump. I have a 12 volt relay, and I swappped it out with a few others in the hopes of finding a relay that was not as sensitive. I have tried adjusting the 2 float switches up and down, but I still get relay chatter. Relay is powered by a 12 VDC wall wart. I have a switch for auto / manual fill. So once it starts to chatter, all I have to do is flip the switch to manual for sa couple of seconds, and manually add probably no more than 1/2 cup of water total and the level is sufficient to stop chattering. So by having to do it this way its far from being totoally automatic. I just need to get rid of the chatteriing of the relay...

Any ideas appreciated.......Its used to top off a 20 gal tank, and the lift of the pump is well within the specs for head of the pump

 

[radone]

You could put this on a timer,

Meaning the pump, that way when your ato say it needs water the pump won't run until the timer says to run. If your dosing Kalk this is a better way and to dose at night when the pH drops.

Are your float switches inside of a snail guard setup or just in open water? If in open water the wave action in your sump may be causing this. depending on your float switch and the size of your sump you might consider another switch to act as a low level=turning the pump on and one at high level=turning the pump off. I would also included a very high level which shuts down the whole ATO just to be safe and not flood the floor.

HTH cool:

 

[radone]

http://www.reefcentral.com/forums/showthread.php?s=&threadid=606215

Try this out, it's worked flawlessly for me