U3 Generic Help

Thu, 09/05/2019 - 11:32

#2

LabJack Support

Take a look at the LabJack U3

Take a look at the LabJack U3 quickstart here:

https://labjack.com/support/quickstart/u3

For further help, please provide more details on what you need help with.

Fri, 09/06/2019 - 03:31

#3

Helait

I had attached a pdf file ...

I had attached a pdf file .....

Fri, 09/06/2019 - 10:24

#4

LabJack Support

When you post on this forum,

When you post on this forum, you will not see your post until we approve it. That's how we keep spam off the forum.

Fri, 09/06/2019 - 12:31

#5

LabJack Support

Try posting your pdf now. It

Try posting your pdf now. It wasn't an allowable file type when you first posted, but it is now. Also, I removed some of your previous repeat and test posts.

Mon, 09/09/2019 - 00:51

#6

Helait

I upload a PDF file......

I upload a PDF file......

File Attachment:

This is my first experience with this type of equipment.pdf

Mon, 09/09/2019 - 16:20

#7

LabJack Support

It looks like you are using

It looks like you are using stream mode. Read the following to make sure you do indeed want to use stream mode:

https://labjack.com/support/datasheets/u3/operation

I suggest you use the Test panel in LJControlPanel for your initial troubleshooting and testing of the U3 and your signals. Use known software so you don't have the added confusion of your own software.

1) Temperature:
With the same conversion formula I do not read the same values between the
application of Labjack and mine;
The temperature fluctuates by +/‐ 1.3 ° C;
I should get a fixed temperature to the tenth of a degree and see the increase or
decrease with a tenth of a degree.

So you are trying to read from 2x PT100 RTDs. You have them connected to an LJTick-Resistance-1k that is plugged into AIN2/AIN3.

Do you have a U3-HV or U3-LV? You want to use low voltage analog inputs with the LJTR, so if U3-LV then FIO2/FIO3 is fine, but if U3-HV you want to use a low voltage analog input on FIO or EIO:

https://labjack.com/support/datasheets/u3/hardware-description/ain

See "Resolution" here:

https://labjack.com/support/datasheets/accessories/ljtick-resistance

The math in that example works out to 0.76 degrees C per count, so that is the best you can expect for resolution.

2) Status of digital inputs
Get a reliable reading to operate accordingly.

In your stream I just see you adding 18 analog inputs (AIN0-AIN17). Use the special channel numbers 193 and 194 to get digital inputs:

https://labjack.com/support/datasheets/u3/operation/stream-mode/digital-inputs-timers-counters

Tue, 09/10/2019 - 07:06

#8

Helait

Ok. one thing at a time.

Ok. one thing at a time.
Input stream configuration as follows:

LJUD.AddRequest(u3.ljhandle, LJUD.IO.CLEAR_STREAM_CHANNELS, 0, 0, 0, 0)

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 0, 0, 0, 0) 'AIN0

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 1, 0, 0, 0) 'AIN1

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 2, 0, 0, 0) 'AIN2

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 3, 0, 0, 0) 'AIN3

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 4, 0, 0, 0) 'FIO4

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 5, 0, 0, 0) 'FIO5

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 6, 0, 0, 0) 'FIO6

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 7, 0, 0, 0) 'FIO7

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 8, 0, 0, 0) 'EIO0

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 9, 0, 0, 0) 'EIO1

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 10, 0, 0, 0) 'EIO2

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 11, 0, 0, 0) 'EIO3

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 12, 0, 0, 0) 'EIO4

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 13, 0, 0, 0) 'EIO5

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 14, 0, 0, 0) 'EIO6

LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 15, 0, 0, 0) 'EIO7

So configured its ok.
When I add the instructions for CIO0 and CIO1