Waterproofing float sensors

[Raul-7]

So the caveat of using float sensors is that they fail when submerged.

I notice most of them have a 1/8" thread. Couldn't you use: 1/8"FNPT x 3/8" Hose ID Nylon Female Adapter, add vinyl tubing and that would solve the problem?

 

[slief]

So the caveat of using float sensors is that they fail when submerged.

Is that right?? I must be lucky to have 4+ years on mine without a failure... That or I just use good float switches.. I wonder.. Good float switches is the answer.
If you use good float switches, they should be fine when submerged. Cheap ones, maybe not.

If you are worried about it, get float switches with a longer shaft or use the fitting like you mentioned.
Here is a cheap long shaft switch.... There are a number of others as well.
http://www.amazon.com/100mm-Sensor-...&qid=1417734075&sr=8-87&keywords=float+switch

This one could work for a too high and too low float switch.
http://www.amazon.com/Length-Vertic...qid=1417734139&sr=8-119&keywords=float+switch

They also make bulkhead style switches that you drill a hole into your sump and insert through the hole like a bulk head.
http://www.amazon.com/Tanks-Horizon...8&qid=1417734629&sr=8-2&keywords=float+switch

 

[morty]

I have Madison float switches that have spent their entire "lives" under SW -- one is in a SW reservoir and spends time 4' submerged...

So I agree with slief that it's uncommon for the potting to fail. But the fitting you found is a unique solution and one I will "stick a pin" in. Another approach would be to coat the top of a new float switch with an additional safety blob of silicone glue.

 

[Raul-7]

Good idea. Instead of using vinyl tubing; you could just fill the barbed end with silicone.

I can't wait to get my Apex. Love the fact that you could multiple floats compared to the competitor.

 

[morty]

Good idea. Instead of using vinyl tubing; you could just fill the barbed end with silicone.

I can't wait to get my Apex. Love the fact that you could multiple floats compared to the competitor.

I have ten different float switches connected to my Apex :thumbsup:

 

[slief]

Good idea. Instead of using vinyl tubing; you could just fill the barbed end with silicone.

I can't wait to get my Apex. Love the fact that you could multiple floats compared to the competitor.

Do yourself a favor and get good float switches and not the cheap amazon or ebay ones. The good ones like the ones I use as well as the Madison ones Morty uses are sealed with a hard epoxy so they don't suffer from the water intrusion issues that cause the failures that the cheap ones deal with. They are also better quality and reversible. You remove the clip, flip the float and a normally open float becomes a normally closed float. I prefer the ones I use because they have a single cable coming out of the float which insures a better seal but even the decent two wire ones are reliable. Mine have the 2.5mm plug on the end but if you cut that plug off, there are 2 wires inside the cable that can be connected to the Apex breakout box.

 

[gregr]

A question and a thanks for pointers to those quality float switches. Are these the cheap ones that you're talking about? It's been a little over a year since I installed them, no problems but if they're a weak link I want to replace them with the better ones.
Thanks!

 

[slief]

A question and a thanks for pointers to those quality float switches. Are these the cheap ones that you're talking about? It's been a little over a year since I installed them, no problems but if they're a weak link I want to replace them with the better ones.
Thanks!

Personally, I wouldn't use those however... If they are not fully submerged, meaning that where the wires going into the plastic threaded shaft of the switch is not under water, they should be fine. I would also add a bit of silicone or epoxy to the area where the wires meet the shaft to insure they were well sealed. Water intrusion is the big issue with many float switches.

These are the ones I use. They have a single larger wire coming out the top of them and are sealed with epoxy where the wire meets the switch. Inside the single wire is the two traditional wires seen on you float switches. The single wire makes for a better seal. These are fairly expensive as float switches go but I have never had one fail despite some being fully submerged and I like the 2.5mm plug on the end because it matches my break out box.
http://premiumaquatics.com/products/level-controller-repl-float-sensor-kit.html

 

[gregr]

Ok that's great info- thanks!
I've got a 3 switch ATO- one for low level to trigger the ATO pump, another for high water level to turn things off and a super low one to kill the return pumps just in case the water level gets too low. That super low one is always completely submerged.
I wish I had your breakout box- the mini connectors are a great idea.

 

[morty]

A question and a thanks for pointers to those quality float switches. Are these the cheap ones that you're talking about? It's been a little over a year since I installed them, no problems but if they're a weak link I want to replace them with the better ones.
Thanks!

As I mentioned I mainly use Madison float switches, but I also have three that are just like the ones in your link. And I have an identical arrangement to yours, using three switches for low and high sump level detection and topoff control. For a time, the fully submerged switch was one from e bay and it worked without issue for over a year until I decided to swap it out with a Madison switch and move it to a less mission-critical role (detecting when my skimmate container was full). I think the e bay ones are fine, but I feel more comfortable using higher-quality switches in applications where failure could spell disaster.

 

[slief]

Ok that's great info- thanks!
I've got a 3 switch ATO- one for low level to trigger the ATO pump, another for high water level to turn things off and a super low one to kill the return pumps just in case the water level gets too low. That super low one is always completely submerged.
I wish I had your breakout box- the mini connectors are a great idea.

It's a DIY breakout box that was very simple and cheap to make. Here are the instructions.
http://reefcentral.com/forums/showthread.php?t=1847474

 

[gregr]

Might just have to try that. I've got the dremel and soldering iron. There's an old timey electronics place nearby I can probably get all the supplies right off the shelf too.

 

[slief]

Might just have to try that. I've got the dremel and soldering iron. There's an old timey electronics place nearby I can probably get all the supplies right off the shelf too.

Sounds like you are well equipped for that endeavor. It's really simple and will save you a bunch of money while also making the chore of adding switches simple instead of fiddling with wires into little clip connections. One tip, get some dialectic grease for the 2.5mm plug ends.

Also, think outside the box as far as switches go.. I use garage door opener buttons connected to my BOB to trigger my mix pump. Push the button and the mix pump turns on for one hour. Very handy when mixing salt. You can also use momentary buttons like the garage one to trigger feed timers, cabinet lights or anything else connected to an EB power outlet. :beers:

 

[gregr]

I did a little of that with switches from the store I linked to. When I get some time I'm going to make a few of those boxes and replace the 2 BoBs I have now.

 

[Raul-7]

I just got the M8000 from Madison; it's already pre-sealed with epoxy to prevent water intrusion. Very smart.

 

[Raul-7]

I'm working on a mounting solution for these float switches; I'll post updates once I succeed

 

[morty]

Unfortunately the Madison float valves use a 1/8" NPT (national pipe thread) tapered thread molding, so in order to get them to screw in to a mount, a corresponding 1/8" tap needs to be used for best results.

 

[Raul-7]

Unfortunately the Madison float valves use a 1/8" NPT (national pipe thread) tapered thread molding, so in order to get them to screw in to a mount, a corresponding 1/8" tap needs to be used for best results.

http://www.amazon.com/gp/product/B008VJKY7Q/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Wouldn't that work?

 

[morty]

The float valve would thread into that bushing, but note that the bushing would need to be mounted "upside down" for the float to be towards the liquid's surface.

 

[Raul-7]

I understand, I'm using the bushing as a mounting option not for anything else. I'm trying to make a reliable, easy to use mounting solution so others can benefit rather than seeing so many DIY solutions that might be frustrating to source or put together for others. I have all the pieces of the puzzle solved; just waiting on that bushing and hopefully I'll post the results for everyone to benefit.