FX1S-10MR with FX1N-1DA-BD mA trouble

[Stefanoplc]

Hi
We're having issues with an FX1N-1DA-BD Analog output module.
We're using an metallic contamination sensor MCS 1000 to detect particles.
This sends pulses for particles detected in a 30 second time window to a Mitsibushi PLC FX1S-10MR-ES/UL which in turn gets converted from a digital value 0-2000 pulses -> analog value 4-20mA and sends the data to our DCS.
The range is adjusted so that 4mA represents 0 particles, and 20mA should represent 2000 particles.
The problem is that the analog output module never sends an current over 6.42mA.
It starts with 4.0mA then maxes out at 6.42mA long before the max range of 2000.
We can't find a problem in the program and have also tried the example programs in the manual, but still only get a current of 6.42mA

We have also tried 3 different FX1N-1-DA-BD and still get the same results.

Manual FX1N-1DA-BD
Hoping that someone here might have some experience with these modules
Thanks!

 

Edited March 27, 2024 by Stefanoplc

[Goghie]

I already wrote you reply on PLCTalk (https://www.plctalk.net/threads/problem-with-analog-output-fx1n-1da-bd.139641/).

Most likely there it is not up to PLC or PLC card. It can be either bug in program or problem with sensors. Why don't you post program so we can analyze it?

[Stefanoplc]

5 hours ago, Goran Vuckovic said:

I already wrote you reply on PLCTalk (https://www.plctalk.net/threads/problem-with-analog-output-fx1n-1da-bd.139641/).

Most likely there it is not up to PLC or PLC card. It can be either bug in program or problem with sensors. Why don't you post program so we can analyze it?

Thanks for your reply both on this forum and plctalk!
Sorry i didn't realise i got response on that forum.

Today we tried the voltage output mode 0-10V instead of current output mode 4-20mA.
We recieved the correct voltage in the 0-4000 range. Digital value 0 = 0volts and Digital value 4000 = 10v.
However the current output mode still maxes at 6.42mA

The program we tried with were the example programs given in the manual for FX1N-1DA-BD
I have attached a picture of the programs.
We have 3 different FX1N-1DA-BD expansion boards and the mA measurement is the same on all three.
 

[Goghie]

It is almost impossible that 3 cards have malfunctioning current part of analog output. I presume that you changed the wiring for current mode comparing to voltage mode, and forced M8114 to zero?.

 

[pturmel]

Have you examined the load resistance downstream?  Is it within the specs for the output card?  If any receiving component is not isolated, have you checked for DC offset?

[Stefanoplc]

12 hours ago, Goran Vuckovic said:

It is almost impossible that 3 cards have malfunctioning current part of analog output. I presume that you changed the wiring for current mode comparing to voltage mode, and forced M8114 to zero?.

 

Yes we changed the wiring and made sure M8114 was FALSE when using voltage ouput, and M8114 was TRUE when using current output.
We have a PLC in an lab environment and we're simulating difrenent values by writing them to D0 / D2 depending on output mode and measuring the output with a FLUKE.