Hall sensors

For all those wiring gremlins we love, this is the place to discuss them.

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Pete Boole
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Hall sensors

Post by Pete Boole »

If I sited a hall sensor (as a crank position sensor) right next to the starter motor would the starter motor interfere with the signal when cranking?

Pete

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Sirclip
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Re: Hall sensors

Post by Sirclip »

Hi Pete, that's a very difficult question to answer as it depends on the sensitivity of the sensor itself. It might only be answered by a suck-it-and-see test. If you find it does interfere, then you could try isolating the sensor by fitting a magnetic shield around the sensor made from some ferrous material, eg mild steel.
Martin.

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Hawaiis0
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Re: Hall sensors

Post by Hawaiis0 »

I would say yes, as the starter has its own magnetic field and you may cause saturation.

That is a layman's thought based on what I read on google 3 minutes ago.
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Pete Boole
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Re: Hall sensors

Post by Pete Boole »

Thanks guys. That's the conclusion I came to as well after more reading. My idea was to put an anulus of triggers around the flex plate periphery to pick up on but the term flex plate may imply that it does indeed flex? This would constantly alter the sensor gap.

Pete

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DavidOliver
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Re: Hall sensors

Post by DavidOliver »

As Lotusbits have developed injection for our engines, including crank sensor, perhaps Mike can advise/supply.

Dave the cog.

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Pete Boole
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Re: Hall sensors

Post by Pete Boole »

I've already got Mike's kit on another engine but it won't work on the supercharged front end - less space!

Pete

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Hawaiis0
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Re: Hall sensors

Post by Hawaiis0 »

Scarey suggestion. It doesn't need to be outside. Is there scope to rig something inside. I've seen chain driven engines with the cog mechanism inside🤔
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Pete Boole
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Re: Hall sensors

Post by Pete Boole »

The LS1 engine in the Excel had the trigger wheel on the crank - worked great. I think I might have worked it out by having the trigger wheel nested/embedded on the rear of the blower drive pulley. I've finished the pattern for the blower front mount casting which will go to the foundry soon - when it comes back I can get some more measurements taken to see how much space there is.

Pete

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