What can I do about error codes 33487 and 33443 from FieldPoint​.

Question

I am using the AI-111 current module with FP 1600 network module. I checked all wiring and connections and I can't find what is causing the problem.

Answer 1

Ruleo,
It is common to have a reading on a disconnected channel. Generally speaking for measurement devices, un-connected voltage inputs tend to float around to either the positive or negative supply rail of the measuring device and current inputs will float around the 0 mA range. This is due both to device design and the real world behavior of components as opposed to the ideal behavior model. Some devices such as the FP-TC-120, will have circuitry to cause un-connected outputs to go to a specific level (in the case of the FP-TC-120, unconnected outputs will always read full scale of the range).
When you say you are getting a reading on that channel, is it a reading that is close to mininum scale, or is it a reading in the middle of the
scale, i.e. 10.2 mA? If the channel is not reading close to minimum scale, it is possible that the channel has been damaged. On the FP-AI-111, you can use a DMM to measure between the Iin pin and any of the C or Com pins. First disconnect any external wiring to the channel, then hook in the DMM. The resistance (within the accuracy of the DMM) should be exactly 100 Ohms. If the resistance is greater than 100 Ohms, then the channel was damaged by an over-current condition that exceeded the published specifications of the module (30 mA). In that case, the module will have to be sent to National Instruments for repair.
Regards,
Aaron