Level indicator

Greetings,

Hopefully someone has already tinkered with this idea and will supply some helpful information. My fuel oil tank is in the cellar; dirt/mud floor cellar. I'm purposely not on automatic delivery. That way I can control when and how much oil I get.

Problem is, at 74 years old, I have to schelp down really creaky cellar stairs and wade through ankle deep mud to check the Mickey Mouse designed level indicator which may or may not be telling me the truth. I may need to do this more than once during an oil fill cycle to make sure I'm not above 1/2 tank or haven't gone below 1/4 tank.

It seems like I could use a pressure sensing device like one used in a top loading clothes washer to illuminate an indicator light mounted next to the thermostat that would be activated when the level goes below 1/4 tank. It would need to address a N/O relay that would close when the washer device thinks the 'water' level to be less than adequate.

It would work in reverse of its original intent of course but, even if the hose were to fail, there would be no danger of oil shorting out the device since oil isn't electrically conductive. It would make a mess on the floor but the floor is already a mess.

Any suggestions will gratefully accepted.

There are lots of oil tank senders/remote display setups available. Some under $100. I could help you design something that would give you remote indications of fuel level. You could use the resistance between a bare copper wire suspended in the tank and the tank. Resistance would go up as the fuel went down and when the fuel drops below the end of the wire it suddenly goes way up.
The Fuel Minder Store Remote Gauge Products: Fuel Minder, OEM Rocket, Oil Alert, Krueger Sentry, Petrometer, National Magnetic, Floats, tanks
Not associated and have no experience with these systems but they sound like a perfect solution.

Or a magnet on a doughnut shaped float around a tube with magnetic reed switches at different depths that would light an LED for you.

Hello,
Here's a wireless gauge that has good reviews...
https://www.supplyhouse.com/OEM-7000...SABEgIJ5fD_BwE

The first job that I had was working for a fellow who restored antique Franklin cars. The gas gauge was operated hydrostaticaly. A tube was suspended from the sender unit with the bottom open to the fuel holding a collum of air. As the fuel went up in the fuel tank during filling the pressure in the tube went up, the fuel seeks to displace the air causing pressure in the tube to rise above atmospheric. The tube was connected to a u tube in the gauge on the dash with capillary tubing. The pressure from the tube would push liquid down on the back side of the u tube causing the liquid to rise on the front side of the u tube, the front side of the u tube exposed to atmospheric pressure. More fuel, more liquid visible in the front side of the u tube. To calibrate the gauge small rods would be placed in the back side of the u tube, less surface area of the liquid presented to the pressure resulting in quicker response of the sight glass liquid in the u tube. This is a rather rough explanation of the principal, but seems to be a good application for your problem. No electricity, no sparks, with patience my old boss would get the gauges Very accurate. Some googling may turn up some more helpful info on hydrostatic gauges. Hope this helps.

If you really want to make a project of it you could use an Arduino controller and an ultrasonic sensor and then the shy is the limit. With the appropriate shield it could even send you warnings to your phone.

Ultrasonic Range Detector Using Arduino and the SR04 Ultrasonic Sensor: 5 Steps

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Originally Posted by nhengineer

Greetings,

Hopefully someone has already tinkered with this idea and will supply some helpful information. My fuel oil tank is in the cellar; dirt/mud floor cellar. I'm purposely not on automatic delivery. That way I can control when and how much oil I get.

Problem is, at 74 years old, I have to schelp down really creaky cellar stairs and wade through ankle deep mud to check the Mickey Mouse designed level indicator which may or may not be telling me the truth. I may need to do this more than once during an oil fill cycle to make sure I'm not above 1/2 tank or haven't gone below 1/4 tank.

It seems like I could use a pressure sensing device like one used in a top loading clothes washer to illuminate an indicator light mounted next to the thermostat that would be activated when the level goes below 1/4 tank. It would need to address a N/O relay that would close when the washer device thinks the 'water' level to be less than adequate.

It would work in reverse of its original intent of course but, even if the hose were to fail, there would be no danger of oil shorting out the device since oil isn't electrically conductive. It would make a mess on the floor but the floor is already a mess.

Any suggestions will gratefully accepted.

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Your solution would work, but anything that can leak eventually will and cleaning up a spill in a muddy basement would be a nightmare -- and if you don't clean it up the stink will be unpleasant. I was once on a technical advisory board for oil heat research. A saying in the industry is: "oil stinks, gas explodes".

Another solution that could not cause an oil spill would be to use an ultrasonic sensor looking from the top to sense the level of the oil in the tank. Such sensors are available very inexpensively, e.g., $2.99 at
https://tinyurl.com/y7zwej58.

You would need some additional electronics, though, and a simple power supply -- which could be just some AA batteries. Perhaps you know of an "electron" near you that would enjoy helping you with this. If you lived near me, I love little projects like this -- but I'm in MN. BTW, at 74, schlepping up and down the cellar stairs is good for you unless you have disabilities or the creaky stairs are dangerous for you. At 76, I no longer zoom up and down the stairs like a horny teenager about to miss a phone call, but I do eventually get there. Did two loads of laundry today -- 4 trips up and down. Changed my sheets today. It ain't Easter yet but I don't like to wait until the last minute, ya know...

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Originally Posted by Sleykin

Or a magnet on a doughnut shaped float around a tube with magnetic reed switches at different depths that would light an LED for you.

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This is an excellent idea, better than the ultrasonic approach that I suggested. Simple and cheap. He'd only need one reed switch if he only cares about a "go-nogo" indication. Reed switches are hermetically sealed and made of glass so they can tolerate immersion in oil with no problem. Sliding sensors like this can be problematic in water because of mineral buildup, but should work very nicely in oil. Things in a oil tank can get cruddy too, but not like in water.

Well done, Sleykin!

nhengineer and Sleykin: I'd be glad to correspond. I have both reed switches and magnets in my goody box and I'm willing to share. I'm a widower since 2011 so I keep very busy, but I check email often even when travelling. I'm outta this MN icebox for the FL keys next Monday for some bluewater fishin', but I'll have my laptop and I do keep up with email. If y'all care to correspond, pls use this addy:

dforeman2x3@goldengate.net

Delete the 2x3; that's there only to deflect spam bots that don't actually read the material they scan for email addys.

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Originally Posted by Sleykin

There are lots of oil tank senders/remote display setups available. Some under $100. I could help you design something that would give you remote indications of fuel level. You could use the resistance between a bare copper wire suspended in the tank and the tank. Resistance would go up as the fuel went down and when the fuel drops below the end of the wire it suddenly goes way up.
The Fuel Minder Store Remote Gauge Products: Fuel Minder, OEM Rocket, Oil Alert, Krueger Sentry, Petrometer, National Magnetic, Floats, tanks
Not associated and have no experience with these systems but they sound like a perfect solution.

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Wow, there's quite a few to choose from in your link but even $100 is a bit of a stretch for me. I think I can make one for next to nothing from scrap bin parts (like I make everything else).

Regarding the resistance wire idea, how can that work? Oil is not electrically conductive.

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Originally Posted by Ed.Murphy@Dimide.com

Hello,
Here's a wireless gauge that has good reviews...
https://www.supplyhouse.com/OEM-7000...SABEgIJ5fD_BwE

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Thanks for the link Ed. That's surly what I would like to have but it $100 I don't have.

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Originally Posted by garage nut

If you really want to make a project of it you could use an Arduino controller and an ultrasonic sensor and then the shy is the limit. With the appropriate shield it could even send you warnings to your phone.

Ultrasonic Range Detector Using Arduino and the SR04 Ultrasonic Sensor: 5 Steps

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That one is interesting for sure Mr. Nut but it's a bit above my Arduino awareness level right now.

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Originally Posted by Don42

Your solution would work, but anything that can leak eventually will and cleaning up a spill in a muddy basement would be a nightmare -- and if you don't clean it up the stink will be unpleasant. I was once on a technical advisory board for oil heat research. A saying in the industry is: "oil stinks, gas explodes".

Another solution that could not cause an oil spill would be to use an ultrasonic sensor looking from the top to sense the level of the oil in the tank. Such sensors are available very inexpensively, e.g., $2.99 at
https://tinyurl.com/y7zwej58.

You would need some additional electronics, though, and a simple power supply -- which could be just some AA batteries. Perhaps you know of an "electron" near you that would enjoy helping you with this. If you lived near me, I love little projects like this -- but I'm in MN. BTW, at 74, schlepping up and down the cellar stairs is good for you unless you have disabilities or the creaky stairs are dangerous for you. At 76, I no longer zoom up and down the stairs like a horny teenager about to miss a phone call, but I do eventually get there. Did two loads of laundry today -- 4 trips up and down. Changed my sheets today. It ain't Easter yet but I don't like to wait until the last minute, ya know...

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That one would work slick Don and, at $3, I'm ready to try it. I do have, however, a few questions.

#1. The hole in the top of the tank is about 1.6" diameter. The supplier doesn't give the size of the unit. I guess I'd need to buy one on speculation to find out if it would fit through the opening.

#2. In my ignorance, I'm just a little bit concerned about ultrasound bouncing off the side of the steel tank and giving false readings (not that that dumb float on a twisted strip of beer can isn't also giving false readings).

#3. What would I use to measure the time between ultrasonic outgo and input? Can you give me a link?

#4. What would I use to convert that to distance? Can you give me a link?

#5. What would I do to convert the information in #4 to a visual signal? Can you give me a link?

Regarding my cellar stairs, they are even older than I am and it's only a matter of time before they just collapse but, of course, the same can be said for me.

Not sure if it has been mentioned yet but a simple go no go device would be to use a flat float with a wooden dowel mounted vertically a couple of stripes painted on the dowel indicating high and low would do the trick for being able to view the marks without having to go down in the basement could be done with a light and mirrors adjusted so you could see the stick from the top of the stairs. If there is a pathway to the tank by walking there is an optical path which can be directed to be seen use a very small light aimed at the stick and the first mirror will direct a beam to the rest of the mirrors the cost would be next to nothing, and not dependent on any quirky electronics

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Originally Posted by nhengineer

That one would work slick Don and, at $3, I'm ready to try it. I do have, however, a few questions.

#1. The hole in the top of the tank is about 1.6" diameter. The supplier doesn't give the size of the unit. I guess I'd need to buy one on speculation to find out if it would fit through the opening.

#2. In my ignorance, I'm just a little bit concerned about ultrasound bouncing off the side of the steel tank and giving false readings (not that that dumb float on a twisted strip of beer can isn't also giving false readings).

#3. What would I use to measure the time between ultrasonic outgo and input? Can you give me a link?

#4. What would I use to convert that to distance? Can you give me a link?

#5. What would I do to convert the information in #4 to a visual signal? Can you give me a link?

Regarding my cellar stairs, they are even older than I am and it's only a matter of time before they just collapse but, of course, the same can be said for me.

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Don, I found one on eBay for $1 with free shipping. How can they do that?
https://www.ebay.com/itm/1-Ultrasoni...8AAOSw7z1aOcPd

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Originally Posted by Sleykin

Or a magnet on a doughnut shaped float around a tube with magnetic reed switches at different depths that would light an LED for you.

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Good suggestion, Sleykin. Any idea where I'd get a doughnut shaped float to fit through a 1.6" diameter hole?

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Originally Posted by nhengineer

Good suggestion, Sleykin. Any idea where I'd get a doughnut shaped float to fit through a 1.6" diameter hole?

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It need'nt be toroidal.

1.5" diameter wooden cylinder (closet rod?) bored to fit over the tube? Shellac the wood to prevent it becoming waterlogged.

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Originally Posted by mklotz

It needn't be toroidal. 1.5" diameter wooden cylinder (closet rod?) bored to fit over the tube? Shellac the wood to prevent it becoming waterlogged.

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Do you mean to have the magnet attached to the wooden cylinder that is acting as a float? How would I attach the reed switches to the rod?

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Originally Posted by nhengineer

Do you mean to have the magnet attached to the wooden cylinder that is acting as a float? How would I attach the reed switches to the rod?

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I would use a thin-walled plastic tube and cement the reed switches inside it. Plastic caps cemented on the ends of the tube would keep liquid off the switches and provide constraint to keep the wooden cylinder on the tube. The magnets could be cemented into holes drilled in the wooden float.

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Originally Posted by nhengineer

Good suggestion, Sleykin. Any idea where I'd get a doughnut shaped float to fit through a 1.6" diameter hole?

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As Marv said, about any float that isn't eaten by oil will work fine. I have lots of different magnets that would work fine. You would want something on the bottom of the tube to keep the float from falling off the end if the level got too low and also so the float won't drop below the last reed switch. The reed switches would be normal open switches. One switch at 1/2 full and another at 1/4 full. The one at 1/4 full would be the bottom of the plastic or copper tube and would stay lit until the tank is filled. The circuit would be a simple 3 wire 2 AA batteries would operate it just fine. So, all you would need are 2 reed switches, 2 LEDs, the float and magnets and a tube and some wire. I was thinking 3/8" tube would be ideal and the float would not have to be a large diameter. Do you have a lathe or drill press? You could easily make a float out of anything floaty :)

Quote:

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Originally Posted by nhengineer

That one would work slick Don and, at $3, I'm ready to try it. I do have, however, a few questions.

#1. The hole in the top of the tank is about 1.6" diameter. The supplier doesn't give the size of the unit. I guess I'd need to buy one on speculation to find out if it would fit through the opening.

#2. In my ignorance, I'm just a little bit concerned about ultrasound bouncing off the side of the steel tank and giving false readings (not that that dumb float on a twisted strip of beer can isn't also giving false readings).

#3. What would I use to measure the time between ultrasonic outgo and input? Can you give me a link?

#4. What would I use to convert that to distance? Can you give me a link?

#5. What would I do to convert the information in #4 to a visual signal? Can you give me a link?

Regarding my cellar stairs, they are even older than I am and it's only a matter of time before they just collapse but, of course, the same can be said for me.

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#1 If both eyes fit in the hole the entire board would not need to fit.

#2 The ultra sonic beams are focused pretty tight. Would not be an issue.

#3,4,&5 You would need some circuitry to generate pulses to the one input and a decoder to read the time spaces on the output. It could possibly be done with a 555 IC and then something on the output to differentiate the waveforms and measure the time between pulse replies. You could also do it with a simple push button switch to pulse the input and then something to measure the time from the switch push to the return pulse in microseconds. It could be done with analog circuits, but from the website "We recommend the NewPing library to use this sensor with your Arduino or compatible." it is intended to be used with a microprocessor and IO interface. Unless you have something like an early RADAR background, you will need to learn some electronics and math to make it work analog. To make it work right you will need to learn to speak to an Arduino.
I was a Nav Comm tech for the FAA for 35 years and retired 10 years ago. I have let the industry pass me by. I think I could build a circuit to work with this ultra sonic device, but I would have to dust off my slide rule ;)

As Marv said, about any float that isn't eaten by oil will work fine.

I think Delrin will float on oil. I have lots of that. I'll check out the density and compatibility with fuel oil.

I have lots of different magnets that would work fine.

This magnet to be attached to the float, right?

You would want something on the bottom of the tube to keep the float from falling off the end if the level got too low and also so the float won't drop below the last reed switch.

Agreed.

The reed switches would be normal open switches. One switch at 1/2 full and another at 1/4 full. The one at 1/4 full would be the bottom of the plastic or copper tube and would stay lit until the tank is filled.

Lit? Wouldn't the bottom reed switch be NO until the floating magnet was near it?

The circuit would be a simple 3 wire 2 AA batteries would operate it just fine.

Why 3-wire?

So, all you would need are 2 reed switches, 2 LEDs, the float and magnets and a tube and some wire.

Why 2 LED's. Would I only need one (red) to tell me when I'm at or below ¼ tank or would the other one (green) be to tell me that the device was operating properly?

I was thinking 3/8" tube would be ideal and the float would not have to be a large diameter. Do you have a lathe or drill press?

Drill press.

You could easily make a float out of anything floaty.

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Originally Posted by nhengineer

As Marv said, about any float that isn't eaten by oil will work fine.

I think Delrin will float on oil. I have lots of that. I'll check out the density and compatibility with fuel oil.

I have lots of different magnets that would work fine.

This magnet to be attached to the float, right?

You would want something on the bottom of the tube to keep the float from falling off the end if the level got too low and also so the float won't drop below the last reed switch.

Agreed.

The reed switches would be normal open switches. One switch at 1/2 full and another at 1/4 full. The one at 1/4 full would be the bottom of the plastic or copper tube and would stay lit until the tank is filled.

Lit? Wouldn't the bottom reed switch be NO until the floating magnet was near it?

The circuit would be a simple 3 wire 2 AA batteries would operate it just fine.

Why 3-wire?

So, all you would need are 2 reed switches, 2 LEDs, the float and magnets and a tube and some wire.

Why 2 LED's. Would I only need one (red) to tell me when I'm at or below ¼ tank or would the other one (green) be to tell me that the device was operating properly?

I was thinking 3/8" tube would be ideal and the float would not have to be a large diameter. Do you have a lathe or drill press?

Drill press.

You could easily make a float out of anything floaty.

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Delrin sounds perfect as long as it flots and survives in oil.

You might want more than one magnet attached to the float, a bit of experimenting with the reed switches and a magnet will let you know how close the magnet needs to be and how powerful a magnet you need.

Yes. You could just use one reed switch and one LED to tell you when it was at or below 1/4 full. In your original post you wanted to know you were not above half a tank. The second reed switch would be mounted in the tube at half tank with a barrier to keep it from going higher. The second LED would light above 1/2 and stay lit until you were below 1/2 tank. Between 1/2 and 1/4 tank, no LED's would be lit. Below 1/4 tank the 1/4 full LED would stay lit. If you have a thermostat near where you want to mount the LED's, you could use that to power your tank monitor with just a diode and capacitor and a current limit resistor. The three wires would be one common and one for each switch/LED combination. I can post a circuit if you like....and I can figure out how to post a picture LOL

With a drill press, I would use a hole saw to make my float. Just bore it out to an easy sliding fit on the tube you use, but it won't go over the cap on the end of the tube. Put a small hose clamp around the tube to constrain the float to the 1/2 tank level

A float suggestion, a carburetor float from a small air cooled motor, doughnut shaped and ready made for fuel. :)

I can't help wondering if construction would be simplified by moving the switching outside the tank...

Mount the float to a simple rod. Make a fitting for the hole on the top of the tank to act as a guide for the rod. As the float moves, the rod will move up and down outside the tank.

With such an arrangement, small clamp-on actuators on the rod could be made to operate ordinary micro switches held on a frame sitting next to the moving rod.

Such an accessible arrangement would make setting, adjusting and maintaining the switching arrangement easy. In addition, the visible rod and actuators would provide a visual, analog indication of the fluid level.

Just a thought.

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Originally Posted by mklotz

I can't help wondering if construction would be simplified by moving the switching outside the tank...

Mount the float to a simple rod. Make a fitting for the hole on the top of the tank to act as a guide for the rod. As the float moves, the rod will move up and down outside the tank.

With such an arrangement, small clamp-on actuators on the rod could be made to operate ordinary micro switches held on a frame sitting next to the moving rod.

Such an accessible arrangement would make setting, adjusting and maintaining the switching arrangement easy. In addition, the visible rod and actuators would provide a visual, analog indication of the fluid level.

Just a thought.

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I thought about putting the switches outside too. Problem is when the tank is full you will have 3 feet or so of rod sticking out the top unless you go to a lever arrangement to let the float move the rod a shorter distance.

Aside from everything else another very simple solution would be to purchase a fuel tank sender they are adjustable to a large range of motion if he wanted it to show when 1/4 full as the lowest just adjust it to bottom out at 1/4 tank and if he wanted it to show the upper limit at 1/2 tank adjust it to that position A tiny wall wart could provide the power for the sender and gauge a led could be incorporated as well such as a 2 color green /red No need to invent some adriuno (Spelling) program or fabricate an elaborate magnetic reluctor coil set up or even a floating stick as I described.

Check out the following.

Building a Capacitive Liquid Sensor: 8 Steps (with Pictures)

Though it was designed originally for a vehicle fuel tank, it will work for your application.

That is using an Arduino Micro controller, you can add a WiFi shield and send the reading directly to your phone. I love them. Built a little speed indicator for my lathe with one.

Well, a lot of nice electronic solutions so I’ll go down a different path.

All this is based on the assumption the weight of the tank is being held by something not sinking into the mud and the tank is not too far away from where you can mount the tattletale gage.

In simplest terms, the idea is to mount a “load cell” under the tank and run a tube to your observation point. You do not have to carry the weight of the entire tank. One corner or one end is all that is needed. As volume changes weight is affected accordingly. Of course, the gage would have to be calibrated. A dot of nail polish at the two positions should work. “Load cell” could be an old brake cylinder, hydraulic jack, air bag; you get the idea . . . :-)