LED Fuel Gauge

affinite

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Hi All,
The LED fuel gauge on my 1993 Moody 44 doesnt work.
The guage appears to be a "potted" module so probably unservicable.
Does anyone know where I might get a replacement ?

Failing that I think I'll have to fit a conventional dial-type gauge. Current reading from the sender is 180 Ohms with tank pretty full. Is it simply a question of matching the resistance of the guage to the sender? I vaguely remember something about some being logarithmic and some being linear ?

Thanks in advance
Steve
 
Very vague memories... I believe you're right, some log some lin and also some are reverse slope. I think your first port of call should be the Tek Tanks website as they explain what works with what and offer many alternatives.

Rob.
 
Hi All,
The LED fuel gauge on my 1993 Moody 44 doesnt work.
The guage appears to be a "potted" module so probably unservicable.
Does anyone know where I might get a replacement ?

Failing that I think I'll have to fit a conventional dial-type gauge. Current reading from the sender is 180 Ohms with tank pretty full. Is it simply a question of matching the resistance of the guage to the sender? I vaguely remember something about some being logarithmic and some being linear ?

Thanks in advance
Steve

Meantime..
If you know how much fuel per hour your engine likes, fill up, keep an accurate engine hours log, and carry a 20l jerrycan in an aft locker - to cover uncertainties?

Do you have a known resistance value when empty? (or close)
I'm working on a 10 segment bar LED based system for measuring water levels in my boat's soft tanks, where no gauges exist currently.
The system is controlled by simple software and a micro controller, but might be adapted to other purposes.. fuel or other (variable resistance) related levels included. It may sound over -complex for a boat, but is surprisingly simple.

Graeme
 
The system is controlled by simple software and a micro controller, but might be adapted to other purposes.. fuel or other (variable resistance) related levels included. It may sound over -complex for a boat, but is surprisingly simple.

We need to talk, looks like you are a fellow electronics geek :D I've designed a microcontroller based device with a graphical LCD which shows the actual number of litres, or a close approximation before calibration. I'm considering also a 7-segment LED version, but I won't have the prototype ready for a while.

To the OP, my sender unit measures between 5Ω and 180Ω, and if you disconnect the sender it reads full. I assume you checked it is getting power at the LED module. If you were able to measure the resistance, perhaps not.
 
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Hi Steve

Have a look at the tank tender system very easy to install, super reliable and acurate it will also measure multiple tanks fuel, water, waste.

You could always install it with pop rivets :). ( sorry in joke Steve the gentleman that he is gave me a rivet gun recently. Thanks Steve.)
 
If you want to stay with an electrical gauge, I have looked up a few catalogues and the VDO tank level gauges like 321100 list their sender as " 180 ohm", but some other senders are listed as 240 ohm so you might be better to bank on a new sender. These are round gauges so the most difficult part is making the gauge fit in. New senders are not usually difficult to fit if you have access.
 
Hi Steve

Have a look at the tank tender system very easy to install, super reliable and acurate it will also measure multiple tanks fuel, water, waste.

You could always install it with pop rivets :). ( sorry in joke Steve the gentleman that he is gave me a rivet gun recently. Thanks Steve.)


Thanks guys - I might try and resurect some very rusty electronic skills to re-use the existing LED bar array and make up a new driver circuit using an LM3914. Moody owners website suggests a 240ohm sender but doesnt indictate log or lin - anyway long stick and log book will suffice for now :)

John - Yes I was thinking of riveting in a new one but couldnt remember where the gun was ! Hope you are both safe after the recent strong winds. - Will take a look at Tank Tender

Steve
 
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