My Auto Top-Off

[Runner]

Well, I finally put those level switches I bought a few month ago to use. Seeing as how I was out of town on vacation this past week, I was motivated to do something.

My tentative wiring diagram is at this link:
http://reefcentral.com/gallery/data/500/14962CircuitDiagram.jpg

As for parts, I used three of the magnetic reed switches, a 12 VDC power supply (old cell phone charger), a 12 VDC relay with 120 VAC rated contact from Radio Shack, 3/8" tubing (1/4" ID), pure silicone caulk, a PVC double-gang box, receptacle, switch, various PVC fittings, and wire.

I used the 1/4" ID tubing to hold the level switches. They screwed into it fairly snuggly. Before I screwed them in, though, I filled the bottom 2" or so with 100% silicon caulk.

I pulled the tubing for auto top-off through 1/2" PVC tee and used the two 1/2" PVC pipe to rest on each side of my sump. I used a rubber ball to seperate tubes. It is taped in place with white electrical tape. I used three switches total: the LO switch to turn the top-off water pump on, the HI switch to turn the pump off, and the HI-HI switch as a backup pump off switch.

I wired in everything in a double-gang PVC box. The relay fit well behind the receptacle and the switch. I used a soldering iron to terminate the relay wiring. As you can see, I cut the power jumper between the top and bottom receptacle so I could power them from alternate poles of the relay. The switch will energize the top-off pump no matter what position the relay or float switches are in.

And here is the final product (minus the cover plate for the box). I put it over my sump for the last week and it worked like a charm. I had the bottom receptacle running a recirculation pump when the top-off pump was idle.

If anybody would like any help with something similar, I'd be happy to offer assistance. I think the final part total cost was around $45 or so (not including the 12 VDC power supply, which I already had).

 

[dfguild]

Where did you get the reed switches? Also, while I'm pretty handy at wiring I don't know how to read your wiring diagram. Could you elaborate a bit more on how you wired this?

 

[Angela Short]

I just installed the same switches last week before I went out of town for a week. Scarry hugh I got my total set up called AQUAHUB DELUXE kit.
http://www.aquahub.com/store/index.html

It was linked in Marvins reef site is how I found the kit. It is I think $50 for the 3 switches and all the electrical gadjets to hook it up except for a cheapo extension cord I paid .99 for. The instructions were very clear and I had no trouble hooking it up. Mine worked great the week I was gone and got stuck in the "off" position and didn't top off all day the day after we got home. I had killed the main pump and flooded the sump and it must have gotten stuck in the off position is all I can figure from the water being way over the switch. A little shake and its working great since then. I have a MJ 600 powering it also.

Great job Runner figuring out all the parts and peices! I was lazy and just going to ordered it all pre-bagged Actually I found it off ebay after I had been looking at them anyways brand new, never opened with a new MJ600 for $49.99 so I got a little better deal than right from the company.

 

[Angela Short]

BTW How are you keeping the switches vertical in the sump? I think that may be why mine didn't turn itself on when the water dropped. The high water pushed it out of alignment a dab. Mine is just being held on with a cloths hanger till I can get the glue out to secure the holder down in a perfect vertical position.

 

[Runner]

@dfguild: Angela just posted the link to the place I got the switches. I did not take step-by-step wiring pictures, so I'd probably have to show you the wiring in person to be effective if you are not used to reading circuit diagrams. I am really good at talking in strange languages that nobody understands (that's the engineer in me). Here is an old image of a standard "pump-up" circuit I posted a long time ago. I'll try to explain it, below. Feel free to post follow-up questions if you need more elaboration of any part of this.

The above diagram shows using all 120 V power for switches and receptacle power here. I changed to 12 VDC on the upper "rung" of logic for the sake of those weenie little switches, though, and my personal safety with hands in the water.

The "CR" is the control relay. The circle with the "CR" in the middle is the "coil" which you energize to make the relay switch change position. The "CR" above the two vertical lines is a normally open switch contact (a standard "ice cube" relay has two of these) that closes when the coil is energized. The lines with the little balls below show float switches that open as water level rises. When the water drops below the LO switch, the relay pulls in and seals in around the switch. When the water reaches the HI switch, it breaks the circuit and drops the relay out. Just follow the lines like you would a water pipe from the L1 (120V) size to the N (neutral) side. Add one more "Upper Float Switch (UFS)" and change the power source for the relay and switches to 12 VDC from the cell phone battery charger, and you will see the circuit I used to make my auto top-off.

@Angela: The tubing I used is very stiff and I have about 2" difference in length between the LO (on) switch and the HI (off) switch. I suppose the on switch could eventually float up above the off switch and make the system fail. Thanks for pointing that out. I think I'll find a small piece of PVC pipe and strap it to my LO switch to keep that from happening.

 

[Angela Short]

I think the PVC would work fine for that. I used the mold a hold molding stuff they sent and it worked pretty good. It was a trick to get molded and held just right till it set back up hard. My little float got hung up in the OFF position for some reason like it was not vertical perfectly and got a snag keeping it from slipping down with the water level going down. Pretty good top of for the money though!

 

[Runner]

Bump for Eddie.

 

[Runner]

Here is another bump for the auto top-off. This is generally the way we did it today in the meeting. The circuit diagram is a little off, though -- we used 12 VDC going to the relay rung in the circuit and added an extra high level switch.