Sign in to follow this  
Followers 0
edgarsky

A2NCPU Communication Port

5 posts in this topic

Hello! I have a problem with our A2NCPU it does not communicate to PC anymore, when I about to upload the medoc program by using cable RS422, it says that "no reply from PLC-system", I'm just wondering why the plc port cannot communicate anymore? is there a way to repair the communication port of A2NCPU? I suspect that when I connected the MAC50 display to the PLC, it caused the damaged of the PLC's port, assuming the communication is damaged already, is there anyway to repair it? what is the alternative solution for this in order to load the medoc program project? please help me. your response is higly appreciated. thank you.

Share this post


Link to post
Share on other sites
Are you certain the problem is not the cable? The A2N uses an RS422 serial port, so the communication cable should have RS422 to RS232 converter electronics inside. The proper cable is the SC05 or SC09.

Share this post


Link to post
Share on other sites
Hi Crossbow! Exactly, SC05 is the cable I am using, but lately the PLC is no longer communicate with PC, I checked the serial port of PC and the SC05 cable, nothing problem there. I really confused why a simple problem like this cannot solved. How can I load the new program if there's is a problem on commnication? Please I need your help.

Share this post


Link to post
Share on other sites
Perhaps your SC05 is bad? The unit has electronics in it to convert RS422 to RS232 for the PC end. It is also possible that something has happened and the PLC is no longer putting out the 5VDC required by the cable. Try another cable. If that's not it, the PLC might be damaged.

Share this post


Link to post
Share on other sites
Check your serial comms settings in Medoc. On the older screens and older PLCs, you would often use different RS232 serial settings if talking to the PLC in transparent mode through the screen than you would when talking direct to the CPU port. Try 9600, 8, odd,1 for a starter. I have also seen cpu ports where the pins have corroded, and a gentle squirt of WD40 has restored the comms.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0