Sick and tired of level switches failing!

[Seth81]

So in my sump I use a float style level switch for top off, another for water change, plus I use another one for a low level switch to protect my pump for a total of 3 level switches. I uses these super cheap float switches see pic below. Well in the past year I have had three of them fail! Usually while I am out of town! I think the problem is that the seal eventually fails and salt water gets into the switch as the water level is usually above most of the switches the entire switch is submersed. Probably these switches are not supposed to be fully submersed, but for a low level switch the only other option is to use a right angle switch and drill a hole in the sump, which also allows for no adjustment on switch position.

So today I have decided to spend some cash and buy an ultrasonic level transmitter. Does anyone have any suggestions on an affordable one?

http://www.canreef.com/vbulletin/picture.php?albumid=735&pictureid=6314

[Cal_stir]

I bought one of these, i actually modified it to shut off my skimmer if my sump gets low. works well.

http://spectrapure.com/AQUARIUM/AUTO-TOP-OFF-WATER-LEVEL-CONTROL/Power-Switching-Level-Control

[kole]

I don't know where you can get an ultrasonic level transmitter but I use the same type of switch that you have pictured.
I use it with my ATO. I cut a hole in the top of plastic bottle cap and pushed the wire end through the hole in the cap and secured it with the plastic nut. I then thread the wires through a hole I made in the plastic bottle then screwed the cap on to the bottle. The bottle is upside down and secured to the side of my sump at the correct level for my ATO.

This way the wires are always dry inside the plastic bottle. Haven't failed me yet.

I hope you can visualize it without pics.

[dino]

not a answer to you question but I use a float that requires no power just gravity and its never failed me

[Seth81]

I don't know where you can get an ultrasonic level transmitter but I use the same type of switch that you have pictured.
I use it with my ATO. I cut a hole in the top of plastic bottle cap and pushed the wire end through the hole in the cap and secured it with the plastic nut. I then thread the wires through a hole I made in the plastic bottle then screwed the cap on to the bottle. The bottle is upside down and secured to the side of my sump at the correct level for my ATO.

This way the wires are always dry inside the plastic bottle. Haven't failed me yet.

I hope you can visualize it without pics.

Yeah I could see how that would work, the problem would be securing the bottle in the sump, also I would want it to be somewhat adjustable so I can vary my water change amounts in the future. Could get messy.

[Seth81]

not a answer to you question but I use a float that requires no power just gravity and its never failed me

If it where just ATO then yeah I could figure out a way to just do this mechanically. But its the automatic water change that really requires two switches, or a transmitter.

[Seth81]

Doing a quick search on Ebay and reading some manuals seems like I can get a decent level sensor for $150 - $25 on Ebay. Think I'm going to pull the trigger on this one:

http://www.canreef.com/vbulletin/picture.php?albumid=735&pictureid=6315

Made by flow line, it measures between 2" - 48" with a 3 mm accuracy. Should be good enough. Manual is here if any one is interested.

http://www.flowline.com/pdf/discontinued/echosonic-lu05-lu11-lu12-lu13-m.pdf

[gregzz4]

Are you running 120v through your switches ? This will cook them in short order
They're best used with low voltage
If you must use them on a 120v circuit, check out my thread on how to wire them through a relay

Wiring a float and relay to protect your ATO pump and more (http://www.canreef.com/vbulletin/showthread.php?t=97401)

One of the members posted this sensor link (http://www.sensortechnics.com/en/products/liquid-level-sensors-and-switches/optical-liquid-level-switches/olt/)awhile back

[Seth81]

For my ATO and AWC it's 24 VDC, I use 120 VAC for my SW mixing tank.

Are you running 120v through your switches ? This will cook them in short order
They're best used with low voltage
If you must use them on a 120v circuit, check out my thread on how to wire them through a relay

Wiring a float and relay to protect your ATO pump and more (http://www.canreef.com/vbulletin/showthread.php?t=97401)

One of the members posted this sensor link (http://www.sensortechnics.com/en/products/liquid-level-sensors-and-switches/optical-liquid-level-switches/olt/)awhile back

[gregzz4]

For my ATO and AWC it's 24 VDC, I use 120 VAC for my SW mixing tank.
Hmm, that's odd about the dc ones
I've had a couple low-level switches in my sump for over a year and they are still working
I haven't even cleaned them yet

[scherzo]

I have mine switches wired to a breakout box on my Apex controller. I also put a dab of silicone where the wires entered the body of the switch. 3 years later. No problem.

[Seth81]

I ended up buying that ultrasonic level transmittter, if this works well I may end up replacing a few more of my switches with transmitters :biggrin:

[mkj]

looks promising. Lots of work to set up though and not waterproof only water resistant. In the right setup will work great though.

I like the idea of using it in a stand pipe to reduce water turbulence. That's the issue I have with my sump right now.

[The Guy]

not a answer to you question but I use a float that requires no power just gravity and its never failed me
+1 to this, this is what I'm going to do on my new 120g :peace:

[Seth81]

Thats what baffles are for :biggrin: I move 1200 GPH through my sump with no issues , my water line looks nice and solid. The switches never seemed to be effected by the flow through the sump. Then again I am using an old 90G tank as a sump (with baffleds I built)

looks promising. Lots of work to set up though and not waterproof only water resistant. In the right setup will work great though.

I like the idea of using it in a stand pipe to reduce water turbulence. That's the issue I have with my sump right now.

[mkj]

I have baffles, it has nothing to do with that for me.

It's because I have a small sump return section and my return pump is pulling lots of water which makes small turbulence in last return chamber. In hindsight, I would have make my return section slightly larger but I was trying to max space. My next sump will have an adjustment for this problem. There is a point where return section is too small for how much water is being pulled through, just don't ask me where that point is.

[brizzo]

What is better than 1 cheap float switch? 2 cheap float switches! You can get 5 float switches off ebay for under $10 shipped

[Seth81]

LoL... Yeah I was waiting for someone to say that! In industrial controls we frequently vote between three instruments for a safety critical loop. Only problem is that I need to then have three level switches mounted at the same level, and three discrete inputs into the controller instead of just one. And then also should have some way of warning me that one of three switches has failed.

Yes I could wire them in series, and use a single input, but then that means I'm 3 times as likely to have a failure! IME the switches fail in the closed position so wiring them in parallel would result in a non-fail safe system (i.e. a failure would cause the automatic water change sequence to continually drain)

This transmitter should be Cadillac! Now I just need to find a cheap conductivity transmitter! Ooops...wrong thread:lol:

What is better than 1 cheap float switch? 2 cheap float switches! You can get 5 float switches off ebay for under $10 shipped