5v source for TPS?
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- Lotus-e-Clan
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5v source for TPS?
OK
Without thinking it through I've bought a Weber Alpha TPS for my Wideband Commander Air/Fuel ratio datalogger.
The TPS needs a 5v reference source which is normally provided by an ECU except of course I'm not running mapped ignition or EFI.
So I'm wondering if I could use a 5v car adapter normally meant for in car digital camera charging. Would it be stable enough for a 5v reference.
I haven't got one to test so does anyone know if this would be stable enough...or any other ideas?
Without thinking it through I've bought a Weber Alpha TPS for my Wideband Commander Air/Fuel ratio datalogger.
The TPS needs a 5v reference source which is normally provided by an ECU except of course I'm not running mapped ignition or EFI.
So I'm wondering if I could use a 5v car adapter normally meant for in car digital camera charging. Would it be stable enough for a 5v reference.
I haven't got one to test so does anyone know if this would be stable enough...or any other ideas?
Peter K
You may find that the 5v chargers run somewhat higher, probably depends on each particular charger ..
You could just use a 7805 5v regulator from maplin, part number CH35Q .. stick a 10uf capacitor across the output, maplin part VH22Y will do ... parts total about a quid plus a small piece of stripboard and some wire!
That should give you a nice solid +5v ...
If you're stuck I can build one for you ..
You could just use a 7805 5v regulator from maplin, part number CH35Q .. stick a 10uf capacitor across the output, maplin part VH22Y will do ... parts total about a quid plus a small piece of stripboard and some wire!
That should give you a nice solid +5v ...
If you're stuck I can build one for you ..
- Lotus-e-Clan
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- Joined: Thu Nov 30, 2006 13:25
- Model: Excel SE - EWP/Waterless!
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- Year: 1989
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- Lotus-e-Clan
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- Posts: 4465
- Joined: Thu Nov 30, 2006 13:25
- Model: Excel SE - EWP/Waterless!
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- Year: 1989
- Location: Swaledale
- Lotus-e-Clan
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- Joined: Thu Nov 30, 2006 13:25
- Model: Excel SE - EWP/Waterless!
- Colour: Not Blue or Green
- Year: 1989
- Location: Swaledale
The voltage drop and current draw are so low that a heatsink won't be needed. I'd be surprised if more than 1ma is drawn through the pot ... which means the regulator is dissipating around 1/100th of a watt. Way under the heatsink required line n the tech specs!
We could probably have used a smaller regulator too but you now have a nice 5v source with 999ma spare capacity and it's only 13p dearer than a 0.1 amp regulator!
We could probably have used a smaller regulator too but you now have a nice 5v source with 999ma spare capacity and it's only 13p dearer than a 0.1 amp regulator!
- Lotus-e-Clan
- Senior Poster
- Posts: 4465
- Joined: Thu Nov 30, 2006 13:25
- Model: Excel SE - EWP/Waterless!
- Colour: Not Blue or Green
- Year: 1989
- Location: Swaledale
I've got the Innovate LM-1 wideband controller and LMA-3 aux-in box and was planning the same thing, to feed in the TPS into the aux box (or LM-1) so that it will log TPS v RPM v Air Fuel to help map tuning! The LMA-3 will also log lateral and fore/aft G force too so I could probably calculate all the 20mph acceleration bands in all the gears too ...
So many plans .. I just need to get on with it, the weather is better so it's time to tinker!
So many plans .. I just need to get on with it, the weather is better so it's time to tinker!
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- Lotus-e-Clan
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- Joined: Thu Nov 30, 2006 13:25
- Model: Excel SE - EWP/Waterless!
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- Year: 1989
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I nearly bought the one that steves got but the permanent in-car 52 mm AF ratio guage swayed me toward the Wideband Commander, it's really handy. However the G force bits aren't available with the Wideband Commander so steves got a valuable tuning aid there.
The other downside is that I've got the WBC permanently installed in my Clan so I haven't used it with the Excel as yet!!
Also I got it cheap on ebay second hand....£120 virtually unused with a new weld-on manifold boss.
The WBC has a programable output to control relays (like water injection or other devices) although I haven't dreamt up a need for that yet.
The other downside is that I've got the WBC permanently installed in my Clan so I haven't used it with the Excel as yet!!
Also I got it cheap on ebay second hand....£120 virtually unused with a new weld-on manifold boss.
The WBC has a programable output to control relays (like water injection or other devices) although I haven't dreamt up a need for that yet.
Peter K
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- Senior Poster
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- Lotus-e-Clan
- Senior Poster
- Posts: 4465
- Joined: Thu Nov 30, 2006 13:25
- Model: Excel SE - EWP/Waterless!
- Colour: Not Blue or Green
- Year: 1989
- Location: Swaledale
Cobbles! (it hasn'tchanged) Nice location but nowhere to fettle a Lotus...what with the gradient and cobbles ...and not many houses with garages down there!Pete Boole wrote: p.s. I used to live on Bargate in Richmond!
A/F ratios are very useful but I still reach for the coloutune plugs to see whats really going on in each cylinder.
Peter K
- Lotus-e-Clan
- Senior Poster
- Posts: 4465
- Joined: Thu Nov 30, 2006 13:25
- Model: Excel SE - EWP/Waterless!
- Colour: Not Blue or Green
- Year: 1989
- Location: Swaledale