Wiring a float and relay to protect your ATO pump and more

[Alberta-newb]

Excellent write up! Clear instructions are appreciated.

I will be doing a retro on my ato myself soon. I am using a gravity feed reservoir as my tank is an in wall, and the sump and hardware are behind in an unseen area. My current setup uses a simple float valve (like the Eshops brand but a cheaper humidifier float) it plugs quite often and is unreliable so I picked up an optical sensor and a direct acting 12v solenoid valve. My question is if you can recommend a good relay? The sensor is only rated at 100ma (5-15vdc) but the valve is rated at 400ma. Will a larger relay like you have used work or should I look at some "mini" one with lighter load ratings. The power supply I was going to use is a 12v 500ma.

Any advice appreciated

Francis

[gregzz4]

Thanks for the nice feedback

You could always get a power supply rated the same as your valve
My floats are rated @ 500ma, but my power supply is 600ma
Maybe I'll have an issue down the road, but I doubt it
It's not like I'm pumping 120vdc through them

Sure you can use a lighter load relay, such as a 5 amp
It'll save you a few bucks

I chose the larger one due to the heater and powerhead, and wanted all my parts interchangeable
You can even use an automotive relay for the 12vdc stuff, but it cannot be used for a 120vdc circuit
You could connect the wires to it without a socket and screw it to the wall/stand somewhere

There are also less expensive sockets, but they are not surface mount and do not have screw terminals - solder tab socket

I just noticed I linked the wrong 12vdc power supply - I'll have it fixed
I grabbed the box for our router supply by mistake

[gregzz4]

Originally Posted by Alberta-newb

I picked up an optical sensor and a direct acting 12v solenoid valve

Can you link these ?

[Alberta-newb]

Originally Posted by gregzz4

Can you link these ?

I was on EBay the other day and found the sensor from a Canadian seller for $5, it's one of these: http://www.sensortechnics.com/en/pro...-switches/olt/

The solenoid valve was another EBay purchase, I had to go with a "direct acting" valve as I'm using a gravity feed with virtually no pressure. If I was using a pump, the more common diaphragm type would work (requires about 3 psi typically)

[gregzz4]

Interesting switches
Thanks for the link

[gregzz4]

Quick update

Last Sat night I meant to top up the ATO tank, but a box of beer got the better of me
I went into my office (sump room) Sun morning to do something and the flashing LED was there to remind me of the low level

Gotta like it

[Seth81]

Originally Posted by Alberta-newb

I was on EBay the other day and found the sensor from a Canadian seller for $5, it's one of these: http://www.sensortechnics.com/en/pro...-switches/olt/

The solenoid valve was another EBay purchase, I had to go with a "direct acting" valve as I'm using a gravity feed with virtually no pressure. If I was using a pump, the more common diaphragm type would work (requires about 3 psi typically)

I have to tell you that I have had some really bad luck with diaphragm valves. But if you are running RO/DI water through it you should have no problems. But I ran water to be disposed of, and I kept ketting crap growing in the valve and sticking it open!