non pico pressure transducers

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LucaB
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Re: non pico pressure transducers

Post by LucaB »

leemack wrote:I don't know much about in cylinder pressure checks but doesn't the wps500 also measure negative pressure during a running compression test.
Hi, You are right by the rush I had not thought.

Try this probe

I repeat only work if the data entered on the relationship tension / pressure are correct and if the sensor is linear.
Robski wrote:How would that go on with in cylinder pressure ?
I do not understand question, my English is bad.
Apply otherwise

Best regards
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Transducer Snapon by -30 to 500PSI.psprobe
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LucaB
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Re: non pico pressure transducers

Post by LucaB »

Hi, I forgot, if the sensor signal is not linear but logarithmic put voltage values for the different presses that then try to do probe.

Best regards

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Robski
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Re: non pico pressure transducers

Post by Robski »

LucaB wrote:Hi, I forgot, if the sensor signal is not linear but logarithmic put voltage values for the different presses that then try to do probe.

Best regards
my 1/2 Italian is bad.Apply otherwise ??
Hi, You are right by the rush I had not thought.
Rush ????
How would that go on with in cylinder pressure ?
The probe you created never went negative !

leemack
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Re: non pico pressure transducers

Post by leemack »

I configured a probe from the results of a pressure/voltage test but sith the engine running the zero voltage drops negative so the zero psi isn't correct from the start.

Without the engine running the 0psi scsle of 0.5v = 0 psi is correct. I've now got the use of a wps500 instead but it would've been nice to get it working.

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Autonerdz
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Re: non pico pressure transducers

Post by Autonerdz »

leemack wrote:I configured a probe from the results of a pressure/voltage test but sith the engine running the zero voltage drops negative so the zero psi isn't correct from the start.

Without the engine running the 0psi scsle of 0.5v = 0 psi is correct. I've now got the use of a wps500 instead but it would've been nice to get it working.
You have now proven to yourself the problem with most transducers out there. You cannot make a custom probe for a transducer that is inaccurate. They work OK in a static measurement application but are wildly inaccurate under dynamic conditions such a running compression test.

As far as I know, there are only three transducer choices that don't have this problem. The Pico WPS, the Fluke PV350, and the DCTI. We did extensive testing here on dozens of transducer candidates for the developer of the DCTI and found them all problematic. He ended up having one custom engineered. Of these choices, the WPS is the most versatile.

Tom Roberts
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The ONLY PicoScope automotive specialists in North America

leemack
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Re: non pico pressure transducers

Post by leemack »

Tom Roberts,

thanks for that as I thought I was going mad, so it appears it wasn't really made for the specific task I was attempting to carryout. Even with the snapon scope it proved inaccurate.

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Autonerdz
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Re: non pico pressure transducers

Post by Autonerdz »

leemack wrote: thought I was going mad,
I am familiar with that feeling. :roll:

You are welcome.

Tom

madhuridixit
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Re: non pico pressure transducers

Post by madhuridixit »

Am using PICO WPS500X Automotive Pressure Transducer (PP652) but the drop of voltage is very huge. How to rectify my issue???

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