PT-104 misreading on two channels

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dan acres

PT-104 misreading on two channels

Post by dan acres » Tue Dec 12, 2006 11:09 am

A while ago we purchased two PT-104 units, both functioning . Now it seems that one of the units has decided to read 'low' by approx 1-1.5ºC on two of it's channels (1 and 3).
I've done some experimenting to rule out port, probe software errors:

It's not a port related problem as swapping the units has no effect on which unit is showing the error.
It's not a probe related problem as all the probes have been swapped with no effect.
It's also not a software related problem as my labview program and the bundled PICOlog both agree :roll:

Are there any known issues with the PT-104s suddenly deciding to read low, or more importantly any fixes?

As a side note: I haven't tinkered with any calibration data as far as i'm aware, unless using the bundled labview example (which doesn't function correctly) can do that...

help much appreciated

Dan Acres


Post by Sarah » Tue Dec 19, 2006 2:29 pm

Hi Dan

Thank you for your post.

There are no known issues with the PT104 so it sounds like your unit may have just developed a fault. If you would like to send this to us for repair then please contact us to obtain a returns number.

Best Regards


Channel reading low 1-1.5 degress

Post by Andrew » Mon Jan 29, 2007 12:08 pm

Hi Dan,

For what it's worth, you are not alone. I have a PT104 that has developed the same "error" characteristic (Channel reading low 1-1.5 degress) between channel 1 and 2. The unit I am using is only a couple of weeks old.

Fortunately, channel 3 & 4 are operating OK so I don't need to return the unit as yet (mid experiment). Can you do me a favour when you complete your return; to enable me to plan return of my unit, could you update your post with how the return/repair went and the time it took to complete(door to door).

Best of luck with your repair and thanks in advance for any info you post.


cdt jim

PT104 misreading 1 to 1.5 C low

Post by cdt jim » Sun Feb 11, 2007 2:35 am

I have 2 PT104's
The first PT104 developed a fault with Ch l reading 1 to 1.5 degrees low. The unit was 18 months old, I use it everyday. I bought a second unit and have returned unit 1 for repairs/calibration. Unit 2 ( now 4 months old developed the same problem. I have been using PT104's for about 4 years now but only driving the PT104's with a USB - serial converter, purchased through my Pico supplier, since 5 months ago. Thats when trouble started. Does this sound familiar or are other users having the same problem using only the serial interface.

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Post by ziko » Tue Feb 27, 2007 3:15 pm

Hi and thank you for your post.

I have not heard of this problem myself. Without looking at the device and the serial cable we cannot really comment on that. If you wish to return the products to us we can certainly have a look at it. If you can email the support email then we can generate a returns number for you.

Kind regards

Technical Specialist

Dan Acres

Post by Dan Acres » Wed Feb 28, 2007 1:13 pm

My issues were using a direct serial connection, not a USB > serial. The returned unit seems to work fine now.

As an aside, now it seems that the unit that wasn't faulty has developed a fault in the last week - random noise of ~ 1ºC seems to have appeared on all 4 channels! This is despite not being touched.

Is it possible that power cuts/PC crashes could damage the units through the serial connection?


Post by Sarah » Wed Feb 28, 2007 3:21 pm

Hi Dan

It's not impossible but it would be quite rare and "unlucky". If you would like that unit looked at then just let us know on

Best Regards

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