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How to reconnect to the AB PLC after the PLC is powered up?

In my program, I have an AB driver that is talking with a 1200 Micrologix PLC. It is working just fine, but sometimes the PLC has to be powered down.


What happens is that after the PLC is powered up again, Lookout still has red crosses over all the variables from the PLC, like not coomunicating with the PLC.


Is there any way to tell to Lookout "go and get it again'?


Is there any way that lookout reconnect to PLC automatically, as soon as PLC 'shows up" again?


Thanks in advance.

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The driver has the parameter "Skip every xx poll after failure". What's the poll rate?

For example, you set poll rate to 1 second, and skip 5 poll requests after failure, then if the communication fails, the driver will poll the device every 5 seconds. The driver actually doesn't know whether the PLC is shutdown or not, it just keeps polling and waits for response. When the PLC is back, the next poll is supposed to be successful. So the driver is supposed to work after the PLC is reset.


If it is serial connection, you can log the serial communication and check if the driver keeps polling. Select Option->Serial port, select the serial port and enable the diagnostic file, input a txt file path and name. The communication on this port will be logged to the txt file.


If your lookout is development server, a workaround for now is to open the driver's property and click OK. This will reset the driver object.

Ryan Shi
National Instruments
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