From Friday, April 19th (11:00 PM CDT) through Saturday, April 20th (2:00 PM CDT), 2024, ni.com will undergo system upgrades that may result in temporary service interruption.
We appreciate your patience as we improve our online experience.
I am using Lookout 5.1 with modbus communication to communicate with RTU units. I often get garbled communication and also No response but then after a period of time the system makes communication and the garbled and / or no response message clears. I am talking about the messages that show up in the window area at the bottom of the screen. What I would like to do is add an alarm in case the system receives the no response and it doesn't clear after x amount of time. What I want to do is determine if I have actually lost communication with the device as opposed to just missing one of the polls. What would be the best way to do this?
Maybe you can use the modbus.CommFail. When the communication fails, CommFail turns ON. Create a DelayOn Timer. On/OFF = modbus.CommFail. Timer delay = 00:10 for example. Then, create an Alarm object to monitor the DelayOn Timer.
I will try this but in the past I didn't receive a Comm Fail only a No Response. Unless I missed something. That is why I wanted to trigger off of the no response. I guess I could do it the same way but it looks like the no repsonse is an analog signal. By the way I am new to Lookout.
The CommFail is a datamember of the Modbus object. You will not get alarm on this datamember, but the alarm of no response. But I think the CommFail should turns ON when there is no response.