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Need Help - Siemens PLC ACX32.000/ALG - External I/O error problem

Need Help - Siemens PLC ACX32.000/ALG - External I/O error problem

Need Help - Siemens PLC ACX32.000/ALG - External I/O error problem


I need your help guys about our Refrigeration Plant system problem,. First of all I have a very little knowledge about PLC.

The system consists of Proface GP2300 (operator display interface) connected to Siemens PLC ACX32.000/ALG with 3 units of Siemens Ext. Module ACX42.12/ALG (I/O-1, I/O-2 and I/O-3).

The system is working normally but everyday, like once or twice a day, it will give an alarm of “External I/O 2 error” sometimes “External I/O 3 error” or “External I/O 1 error” and sometimes 2 of any of them. I assumed they referring to the 3 Siemens Ext. Module.

This alarms is intermittent and will disappear or return to normal stage just less than a second but I need to acknowledge first. I tried to check the serial connection between them and even replacing the cable, and also check each power supply DC-24V connections, but everything is seems normal.

My suspect is the Siemens PLC ACX32.000/ALG.

My question is if ever I will replace the said PLC, Do I just need the following procedures?
1. Power OFF the system.
2. Disconnect all the PLC connections.
3. Remove the old PLC
4. Install the new PLC and reconnect all the cables
5. Power ON the system.
6. And that’s it?
The program will just automatically downloaded to the new PLC by the Proface GP2300 and the system will work right away? Even I use an old and used PLC (coming from our other HVAC system)?

Thank you in advance...

RE: Need Help - Siemens PLC ACX32.000/ALG - External I/O error problem

You may get a better response posting this in the "HVAC/R engineering" forum. The SAPHIR product you have is more of an OEM specialised refrigeration controller. I think it is a push to call it a PLC and more 'an application controller pre-defined by Siemens guys wanting to control that specific refrigeration plant in their specific way'.
I would suggest also this product is obsolete, so support will be limited. Maybe contact the company who supplied the refrigeration system as they would typically define the functionality in their particular way.
Sorry I cannot be any more help.

RE: Need Help - Siemens PLC ACX32.000/ALG - External I/O error problem

@ ozmosis

Thanks man, will follow your advicesmile2...

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