Tank liquid level senders

[olewsaa]

Originally Posted by sailormed

You could install a water meter on the outflow of the tank and keep track of volume consumed. Maybe reset when you fill the tank to keep it easy.

Our Ovni 395 has this installed and we are very satisfied with it. Easy to tell how mush a morning wash og shave uses, not to mention a dish washing .

[ranger58sb]

Originally Posted by BigAl.NZ

Maybe the new WEMA units are better? What technology does it use?

It's still a float inside a tube, and the varying resistance measurement is what drives the gauge display. The probe is stainless now, whereas at least as late as 2002-2003 it was a plastic thing...

If the probe goes all the way to the bottom of the tank, it's possibly more likely to get crudded up.

If the inlet from toilet and the vent outlet are on the side, the tank will often be as full as it can get before the WEMA float can rise all the way to the top of the tank (and show Full). Changing inlet and vent outlet to the top of the tank can solve that, though.

-Chris

[gamayun]

Originally Posted by BigAl.NZ

I dont know which WEMA unit you have, but the one on our boat is late 80s vintage, and will read 80% one minute then 60% the next. Since the WEMA sender (resistive?) doesnt go all the way to the bottom of the tank, it doesnt factor in the bottom bit, and the tank is an irregular shape, so it doesnt appear to factor any of that in either!! Hence I need something better.

Maybe the new WEMA units are better? What technology does it use?

Sorry. I forgot the OP was asking about a black water tank. The WEMA unit I bought is the SSS-10, which is intended for either fuel or water. I'll be using it for my fuel tank. The float goes up and down on a stainless solid tube. The old one (don't know the brand) was hinged at an angle, which made the gauge very hard to read in any seastate because the float bounced wildly with the side to side sloshing. I'm hoping the "float on a stick" design mitigates that effect but the Simrad sender to my B&G display is intended to make the reading very precise when I calibrate it as I'm filling the tank again in 5-gallon increments. For your water tank, the WEMA unit comes in 1/2-inch increments so it seems you could get a fairly accurate reading as long as it goes as far as the outlet is located. At least you'd know that "empty" is when the pump is about to suck air.

As to the black water tank, I don't have anything on it but I like the idea of getting an ultrasonic unit to eliminate the potential for clogging. A while back, I'd seen something that took its reading off a small wire probe that fed into the tank that I thought would work well, but can't seem to find what that was when I search for it now. My blackwater tank is not easily accessible and it's very small so if a probe were to clog, I'd probably just quit using it and go back to my current guessing method.

[carlosproa]

Does anybody knows if there is a remote fuel sensor for portable gasoline tanks? I have a Moeller Marine[emoji768] 630012LP - 12 Gal. Fuel Tank with Gauge. It sits hidden below the cockpit floor and is a hassle to take a peek at it as it involves removing part of the cockpit floor. Since I am waiting for my Rpi parts to come in, I am thinking if there is anything out there that I can swap the gage for a something remote?

[oldersalt1944]

Originally Posted by oldersalt1944

Google sensalert. Simple outside stick-on sender only shows full or empty. I set mine at about the 3/4 full level. When red light comes on I know I have a few more flushes before heading for the pumpout.
Oldersalt

OOOPS! My post #9 is WRONG. Product name is Sensalevel, NOT Sensalert! Sorry. Good product, easy to install on outside of plastic tank. 3 little wires from sensor to display. Not expensive. Mine just shows if the level inside the tank is above (red light in display ON) or below (red light in display OFF) the sensor. Don't buy it on Amazon, go to the manufacturer to get better documentation and if necessary support.

Good luck...
Oldersalt

[InsuredApple]

Originally Posted by BigAl.NZ

I dont know which WEMA unit you have, but the one on our boat is late 80s vintage, and will read 80% one minute then 60% the next. Since the WEMA sender (resistive?) doesnt go all the way to the bottom of the tank, it doesnt factor in the bottom bit, and the tank is an irregular shape, so it doesnt appear to factor any of that in either!! Hence I need something better.

Maybe the new WEMA units are better? What technology does it use?

Our WEMA fuel sensor does something similar, and it is brand new. It is really frustrating to see the tank levels drop, while we are at anchor, not using any diesel. -- I hear you!

[Dago]

Originally Posted by MickMeck

Having similar frustrations about not knowing tank levels I installed iSeries Tank Monitors on my holding tanks as well as my three water tanks. I couldn't be happier. They work. They install easily. A great price performer.
https://tankedge.com/products.html

Does anyone else have experience with the Tech-Edge iSeries system? I would use it on plastic water and holding tanks. Thanks.

[belizesailor]

Tank Tender, no electronics, no power required, no problems.

Ive had one for well over 20 years...only required minor maintenance a few times.

http://tanktender.com/

[peghall]

WEMA is ok for fuel or water, but their senders go inside tanks...and internal senders will become clogged by the animal fats in waste, requiring removal to clean 'em every couple of years. The first time most people discover they have to do that is when they choose to replace 'em with a system that uses senders that go on the OUTside of the tank.


--Peggie

[peghall]

This is the guy who actually manufacturers the SCAD and SOLO tank monitors.
I guess they resell his product under their name? That is a guess, but I’m nearly certain he’s the actual manufacturer.
https://www.ferriellosales.com/monitoring-systems.html



He was...but sadly Dennis passed away a few months ago and his Profile Systems died with him. The SCAD systems are now made by a different mfr.


--Peggie

[peghall]

Dennis and his wife were my very good friends for more than 20 years...I miss him more than I can say.


--Peggie

[BobHorn]

Considering the SCAD unit. How much trouble is it to calibrate? Tank empty and tank full? I assume just using water. Also considering the Gobius system with 1/4, 1/2, and 3/4 readouts. Unfortunately Defender only sells the Pro version. Really don't need the readout on my phone.

[Howler]

Here’s a cheap and reliable alternative for accessible plastic holding tanks that requires no installation and no power other than the included 9V battery. Get a pinless humidity monitor like the General MM8 for under $50. Set it for “wall”. Slide it down the exterior of the holding tank until the display shows close to 100% humidity, the bar graph turns red and it beeps. That’s the level of black water in the tank. It’s not what the tool is designed for but it works very well.