Fuel sight guage - conversion

What sort of gauge would you connect it to?

This is the web site of the manufactures

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Most if not all senders that have a resistive output range are simple potential dividers that in effect output a voltage that is related to the input voltage and the position of the potential/ variable resistor.

some gauges will react to the current that flows through the variable resistor together wit the internal resistance of the gauge to make up a potential divider.

Some gauges like my fuel and water gauges are 4 to 20mA as the VDO capacitive level sensor. and have associated 4 to 20mA gauges.

The information mostly given is a little misleading as I stated above.

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If you measure the voltage between the G connection on the gauge and the 12V negative that voltage will vary ar the lever fuel sender moves which is moving the wiper on the resistive sender.

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Where you have a float sender like the wena one you posted what you have inside are a series of reed relays and a ladder resistor chain where when the magnet in the float passes one of the reed relays/switch it changes the resistance thus output voltage depending on the height of the float/fuel/water
 
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Top Google hit for "VDO 0-5V fuel gauge": SingleViu 52mm DEF level gauge. 0-5V sender required - VDO Instruments and Accessories

Personally, I think it's simpler to have the information on the plotter than to have to drill holes for a gauge or mount it - on my B&G you can customise the right hand side of the chart display, with one or two rows of readings.

The capacitive sensor I initially posted can be ordered with either voltage or resistance indicator compatibility with the range either way and whatever range you wish.

As I have 2 tank with a single gauge plus toggle switch to which tank
 
Personally, I think it's simpler to have the information on the plotter than to have to drill holes for a gauge or mount it - on my B&G you can customise the right hand side of the chart display, with one or two rows of readings.

Yes, I like information on the NMEA2000 network, but are we sure the OP has NMEA2000?
 
The capacitive sensor I initially posted can be ordered with either voltage or resistance indicator compatibility with the range either way and whatever range you wish.
I like the BEP one you posted, as it seems very flexible - I think it can be programmed to accommodate sloping tanks?

However the capacitance sensor on eBay that @LadyInBed posted seems very affordable, and the 0.5V range seems like a standard one, that can be used with gauges from more than one manufacturer.

I couldn't immediately find pricing for the Fozmula T/LL140 capacitive gauge you posted.
 
I like the BEP one you posted, as it seems very flexible - I think it can be programmed to accommodate sloping tanks?

However the capacitance sensor on eBay that @LadyInBed posted seems very affordable, and the 0.5V range seems like a standard one, that can be used with gauges from more than one manufacturer.

I couldn't immediately find pricing for the Fozmula T/LL140 capacitive gauge you posted.

I agree with you but if the OP can only get to the exiting sight glass the capacitive will fit in the sight glass.

The OP did say he could not get to the top of the tank.

I would enquire prices from Fozmula as it could save post and duties and I think the E bay one supplier will only post to the US so an agent will need to be used as I have done in the past but it costs for a one off supply.
 
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Thanks all for your inputs.
I don't have an NMEA2000 network, I am thinking fixed gauge rather than NMEA or WiFi.
In my searching I have seen analog gauges with calibration pots in.
PS The one I linked to Fuel level sender,capacitive type,no moving,cut to length 4.6"-7", 0.5-5V output | eBay
from the pictures on the left, it looks like it comes complete with a gauge, that's where I saw the calibration adjustment screws.

The picture on the left 3rd one down is the connections and setting perset pots so once its all installed the empty pot is adjusted when the tank is empty so the gauge reads empty. The full pot is adjusted so the gauge reads full when the tank is full.

Its the ame sa the one I have but mine only has 2 electrical connections as mine is 4 to 20mA where the one you show is voltage 0 to 5Vdc output.
 
I think Nigel Calder's book describes a non-electric pneumatic system that uses a small push button manual air pump and air pressure gauge connected via flexible tubing to the top of a tube that reaches the base of the tank (? sight tube with a sealed top).
Pumping air into this tube increases the pressure until air bubbles out of the lower end. Continued pumping does not increase the air pressure and this indicates the liquid level in the tank. A calibration card can convert air pressure to litres.
The system Calder describes has the pump and gauge mounted on a dashboard panel along with a tap to select different tanks.
 
I think Nigel Calder's book describes a non-electric pneumatic system that uses a small push button manual air pump and air pressure gauge connected via flexible tubing to the top of a tube that reaches the base of the tank (? sight tube with a sealed top).
Pumping air into this tube increases the pressure until air bubbles out of the lower end. Continued pumping does not increase the air pressure and this indicates the liquid level in the tank. A calibration card can convert air pressure to litres.
The system Calder describes has the pump and gauge mounted on a dashboard panel along with a tap to select different tanks.

That's the tank tender solution. Tank tender is about 500 USD for a 2 tank system.

Tank Tender Tank Monitoring Systems
 
I use a bubbler device built around a cheap manometer. The other end of the tube has a brass fitting to help weigh it down. It goes in the filler cap to a consistent depth. I calibrated it by filling up an empty tank 5 litres at a time and then taking two sets of measurements 1. while slowly squeezing the bulb, and 2. just lowering without squeezing using the pressure difference of the air trapped in the tube. The second set was more usable when plotted. It's a bit of a faff but helps to give another data point alongside my hours-run calculation. About £30 for the bits.

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