Vision series analog output tolerances...

[Specifisaurus]

Is anyone else having issues with the analog output tolerances on the vision controllers?

We are currently using a v350 controller and running a 4-20mA output to a VFD which requires a fairly precise control level. Using the same program on three different controls we have found that the 4-20mA signal varies upwards of 1/2 mA - 1mA making precise control nearly impossible without testing a ton of units. We are well below the 500ohm limits, and we can see these variances with just a meter with or without load. The wiring when installled is 18AWG, shielded and runs approximately 2 feet.

Any thoughts?

[Emil]

Did you try the units on your desk or only in the field?

Can you try them in free of noise environment?

[Specifisaurus]

All the testing was done in our office at our desk away from any sources of noise. The incoming power was clean and stable.

[Emil]

Please send to support@unitronics.com:

table of results of the test for different output levels - nuber set in PLC and relevant current measured;

S/N of the units;

OS installed;

Maybe some picture of the test circuit.

Having this information, I'll investigate and will give you answers ASAP.

Thank you for your cooperation.

[Specifisaurus]

Thank you Emil, I will get this information together after lunch and send it out right away.

[Specifisaurus]

The information has been emailed, I apologize for the delay.