Testing Hall Sensor

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suprant0010
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Testing Hall Sensor

Post by suprant0010 »

I just finished assembling my MS. It runs good on the stim, I figured the next logical step is to get it connected on a car battery and try to get a real hall signal.

After connecting to Tunerstudio and running on a car battery, I wired up a hall sensor. I don't have it hooked up on a crankshaft yet, but I was just playing the sensor, getting it to cycle by running a magnet past the sensor. I cannot seem to figure out how to test that the MS is recognizes the change in voltage from the sensor as a tooth.

I'm still getting used to Tunerstudio, but I tried the tooth logging function hoping to see some kind of blip on the screen when I cycled the sensor, which it didn't. Am I doing something wrong?
notimaginative
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Re: Testing Hall Sensor

Post by notimaginative »

I had to adjust the potentiometer on the board for the signal strength of my sensor. Sounds like you might too.
trakkies
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Re: Testing Hall Sensor

Post by trakkies »

A hall sensor converts the pulse it receives from the tooth into a straight on/off voltage, so it would be normal to use the opto input.
Dave P, London UK.
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Matt Cramer
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Re: Testing Hall Sensor

Post by Matt Cramer »

Test the voltage coming out of the Hall sensor, then check the voltage at TSEL and see if it flip-flops when the Hall sensor voltage changes.
suprant0010
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Re: Testing Hall Sensor

Post by suprant0010 »

notimaginative wrote:I had to adjust the potentiometer on the board for the signal strength of my sensor. Sounds like you might too.
aren't the potentiometers only for a VR sensor circuit
Matt Cramer wrote:Test the voltage coming out of the Hall sensor, then check the voltage at TSEL and see if it flip-flops when the Hall sensor voltage changes.
Just tested it, TSEL shows 5v volts while the sensor is closed or even with the sensor disconnected, then when I cycle the sensor it changes to about 3.2v. Is this normal?

I'm not sure what other hall sensors are doing, but the signal output on mine is negative.
suprant0010
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Re: Testing Hall Sensor

Post by suprant0010 »

correction to my last post, just noticed my battery was running low so the last test was not accurate, redid it after recharging

it seems that TSEL shows a positive 5v with or without the hall being active...testing the sensor it shows no voltage while closed, and negative 5v when I pass the magnet in front of it, so it appears to work, but has no effect on the TSEL voltage

one thing i noticed that was strange, the tach input wire (pin 24 on the db37), reads negative 4.2v when the MS is powered on...is it normal for that pin to have an output voltage?
notimaginative
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Re: Testing Hall Sensor

Post by notimaginative »

suprant0010 wrote: aren't the potentiometers only for a VR sensor circuit

Yep, I got the two mixed up.
Matt Cramer
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Re: Testing Hall Sensor

Post by Matt Cramer »

How exactly do you have your input circuit set up?
trakkies
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Re: Testing Hall Sensor

Post by trakkies »

The opto circuit - as far as input goes - is simply an LED. It is polarity sensitive and normally expects a positive voltage input to 'light' it, but you can also use a negative one by applying positive volts to OPTOIN and the negative trigger to XG1. Other components in that chain may need altering too according to the voltage. You could also look at the 'extra' manuals for more details of how to do this for various triggers.
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suprant0010
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Re: Testing Hall Sensor

Post by suprant0010 »

Matt Cramer wrote:How exactly do you have your input circuit set up?
I wired it up according to what the manual said for hall sensors.

I followed all the steps on step 50, as well as the jumpers:
TSEL to OPOOUT jumper
XG1 to XG2 jumper
OPOIN to TACHSELECT jumper

I skipped the optional VR circuit as I had no intentions of using one. I haven't done any of the Hall circuit mods yet.
trakkies wrote:The opto circuit - as far as input goes - is simply an LED. It is polarity sensitive and normally expects a positive voltage input to 'light' it, but you can also use a negative one by applying positive volts to OPTOIN and the negative trigger to XG1. Other components in that chain may need altering too according to the voltage. You could also look at the 'extra' manuals for more details of how to do this for various triggers.
So my sensor putting out negative current could be problem then? Probably a stupid question, but will a hall sensor function on reverse polarity? I was thinking I could reverse the ground and 5v ref and maybe get a positive output.
trakkies
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Re: Testing Hall Sensor

Post by trakkies »

They are a solid state device and IMHO won't work if you reverse the polarity. Indeed may fail if you do.
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suprant0010
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Re: Testing Hall Sensor

Post by suprant0010 »

I was doing some more messing around today and got some interesting results...

Seeing as how my MS does run on the stim, I tried powering the MS with the stim, and set the stim rpm to 0. Then I hooked my hall sensor to the tach pin on the stim. I moved my magnet in front of the hall sensor a few times while the Tunerstudio tooth logger was running, and to my surprise I saw several blue bars show up on the screen.

So my sensor works while the stim is powering the MS, but not the battery. Would this have something to do with me not having any other sensors wired in while on the battery? I noticed while not having anything connected to those pins, my tps is reading 30% and my coolant temp is jumping around erratically.
Matt Cramer
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Re: Testing Hall Sensor

Post by Matt Cramer »

Maybe the Hall effect sensor isn't getting power on the car?
suprant0010
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Re: Testing Hall Sensor

Post by suprant0010 »

Its is, I've tested the current at all the wires, it seems the MS just doesn't do anything with the hall signal unless the stim is powering it all.

I'm going to hook up the tps and maybe a few sensors then check for changes.
Garniche31
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Re: Testing Hall Sensor

Post by Garniche31 »

Hi

I think I have kinda same issues with my Hall sensor (distributor) not making any tach signal on Tunerstudio when cranking (MS II connected to car)

have you found any solution from your side, since that time ? I hope so

cheers

Francois

My project : Saab 900 T16 Hall sensor triggering negative side of a single coil via the High current driver circuit
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