One For The Electronic Buffs

General Chat About Electrics, And Ignition Systems.

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Coops
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One For The Electronic Buffs

Post by Coops »

Im looking at building a custom dash with autometer gauges,
the fuel gauge is giving me a headache,

the autometer one works at these settings.
240 ohms empty to 33 ohms full.

the Capri sender reads: (tested 8 senders 6 were all different readings and 2 were the following within a few ohms of each other)
empty: 70-80 ohms,
full: 10-15 ohms

now, can i get the autometer gauge to work with the capri sender?


Regards Tony C (COOPS)
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MS2 V3.57 Ecu mapable efi and wasted spark ignition.
Procharger D1SC supercharger and Cossie RS500 Intercooler @ 14psi of Boost. 416 RWHP, (boost leak)
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ChrisJC
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Post by ChrisJC »

I think you'd need a little op-amp circuit.

But there must be some little box of trick you can buy already, as it must be a common problem???

Chris.
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r2d2hp
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Post by r2d2hp »

If you look at Elliot's Digital Fuel Gauge >> http://www.mez.co.uk/ms13.html#fuelgauge it should be possible to replace the leds with semiconductor switches.

As each switch is turned on it could enable a divider circuit and then therefore the voltage seen by the fuel gauge. Its something I have to do to mine when the car return home in a weeks time.

Will try and draw a picture so you can see what I mean. Maybe some others could confirm it will work ok.
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Post by ChrisJC »

Here's my suggestion:
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It assumes that your new gauge has no internal resistance (i.e. it needs to see 360mA to give a full reading, and 50mA for an empty reading). This circuit sinks approximately those currents for 80/10ohms on the tank resistance.

Of course you need a handy mate who can understand the cct, work a soldering iron, and fill in the blanks (e.g. choose a single supply op-amp, and add some decoupling).

Chris.
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Coops
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Post by Coops »

cheers guys will ask a mate who is good with electronics, unless someone else has any ideas?
Regards Tony C (COOPS)
Image
MS2 V3.57 Ecu mapable efi and wasted spark ignition.
Procharger D1SC supercharger and Cossie RS500 Intercooler @ 14psi of Boost. 416 RWHP, (boost leak)
Forged 4.8 V8 kitted out with the dogs Cajones of parts. :D
Sponsored by: www.v8performanceparts.co.uk, www.interpart.biz, www.caprisport.com & www.baileyperformance.co.uk
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monty man
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Post by monty man »

yeah ok m8 i'm sure i can work somthing to get it working.
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Ian Anderson
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Post by Ian Anderson »

Tony

do the guage makers not also make a transmitter?

Probably easier to buy a "matched" set than play around with electronics.
(But then I cannot see electricity so can't understand it!)

Ian
Last edited by Ian Anderson on Sun Mar 30, 2008 6:07 pm, edited 1 time in total.
Owner of an "On the Road" GT40 Replica by DAX powered by 3.9Hotwre Efi, worked over by DJ Motors. EFi Working but still does some kangaroo at low revs (Damn the speed limits) In to paint shop 18/03/08.
Coops
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Post by Coops »

yeah they do a matched sender,
but when they room is limited and the sender they use is for a top mounted tank and my sender is a side mounted one,
there is no room to put a sender into the top of my tank, as it will foul the boot floor,
Regards Tony C (COOPS)
Image
MS2 V3.57 Ecu mapable efi and wasted spark ignition.
Procharger D1SC supercharger and Cossie RS500 Intercooler @ 14psi of Boost. 416 RWHP, (boost leak)
Forged 4.8 V8 kitted out with the dogs Cajones of parts. :D
Sponsored by: www.v8performanceparts.co.uk, www.interpart.biz, www.caprisport.com & www.baileyperformance.co.uk
Coops
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Re: One For The Electronic Buffs

Post by Coops »

thev8kid wrote:Im looking at building a custom dash with autometer gauges,
the fuel gauge is giving me a headache,

the autometer one works at these settings.
240 ohms empty to 33 ohms full.

the Capri sender reads: (tested 8 senders 6 were all different readings and 2 were the following within a few ohms of each other)
empty: 70-80 ohms,
full: 10-15 ohms

now, can i get the autometer gauge to work with the capri sender?

found this autometer gauge tonight,

Auto Meter 5715 - 2-1/16 Electrical
Phantom Fuel Level Gauge 2-1/16" electrical 73-10 ohms Fits most pre-1989 Ford vehicles and most Chrysler vehicles
2-1/16 Electrical
Item# 105-5715
Only $39.99

so i may of solved my problem :lol:
Regards Tony C (COOPS)
Image
MS2 V3.57 Ecu mapable efi and wasted spark ignition.
Procharger D1SC supercharger and Cossie RS500 Intercooler @ 14psi of Boost. 416 RWHP, (boost leak)
Forged 4.8 V8 kitted out with the dogs Cajones of parts. :D
Sponsored by: www.v8performanceparts.co.uk, www.interpart.biz, www.caprisport.com & www.baileyperformance.co.uk
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