Tiggy / Robor fuel gauge systems

[flyingfergus]

Any body got the Tiggy fuel flow sesnsor system from XCshop or the Robor fuel flow sensor system from UKPPG ?

I had understood that due to the pulsing of the fuel they are less accurate (+/- 10%), On a 10 litre tank of fuel thats a litre out.

I would be interested to know any one who has one & what accuracy have found especially if its on a 4 stroke before I part with the hard earnt readies

Paul C

[flyingfergus]

Hi Sticky,

The interest in the "flow" sensor system is that it should in theory help understand the most effiecient fuel consumption. Seeing the spot fuel consumption for each wing setting should help in decide which is the best option to acheieve the desired goal.

However if they are not accurate then like you say a cheap mirror is just as good.

regards

Paul C

[bigpapa]

I like the idea of one of these gauges, but this one looks a bit bulky/amateurish and some of the wires look a bit vulnerable.

Mirrors are okay, but I would prefer a more scientific approach with instantaneous consumption and time to empty.

[ptwizz]

If your interest is in instantaneous fuel consumption, an instrument with a 10% uncertainty is virtually useless.

As a general rule for test equipment, the instument should have an uncertainty better than 1/10 of the difference you intend to measure. This means that if you think a particular trimmer setting might give a 5% improvement in consumption, you would want a sensor to read with an uncertainty better than 0.5%.

An instrument with 10% uncertainty will tell you if fuel is flowing or not, but I wouldn't trust it much further than that.

[bigpapa]

I'd be interested to see where the inaccuracies come from. It would expect it is related to the sample rate of the electronics.

If the sample rate were 10 x max rpm (~2000Hz) then it should capture the pulse at sufficient resolution to accurately get the fuel flow. I expect it is much lower than this. Does anyone know?

Where does the 10% inaccuracy figure come from, as no one seems to have one!? Which probably means that the 10% is speculation?

[flyingfergus]

I posted the same question on the Yahoo forum & had one reply from a chap who had the Robor. He posted it was very inaccurate but didn't record any figures.

When I investigated 3 years back the issue was around the flow sensor. None of them were designed to measure at the low flow rates we use (especially a Bailey V5). With the flow being a pulse this also adds to the innacuracy. The charts for the flow rates on the sensors I looked at (wihch was not the Robor) showed error up to 10% at our flow rates. As there are a couple on the market now I thought I would see if things had moved on.

Still looking for more feedback for those who have one.

Thanks

Paul C

[bholleran]

I use the flymaster M1 system with a flymaster vario and I think it is brilliant. Albeit expensive.

The M1 needs to be calibrated to the tank that it is fitted to. in any graduations you want up to 30 measurments. So for a 15 ltr tank you calibrate it every 1/2ltr exactly when you first set it up. It interpolates the rest of the points. It transmits this data wirlessly to the vario along with cylinder head temperature and rpm of the engine.

It uses a recargable battery that last for ages.

I have found it to be very accurate. I normally only set the remaining fuel to be visible on the vario, but I think you can set it to show the remaining flight time and average fuel consumption.

I think the average can be set to a short interval so that it is very low. i.e. 1 min, but I would need to check.

[morgy]

Why you Bailey boyz need a fuel meter is beyond me....