about s7 200 communacation port burn

HI,ALL

I have a system with s7200 PLC and GP hmi.when I connect the PLC and HMI,few minites, the PLC's communacation port burn. I think the cabel is good,the PLC and HMI is new. Please tell me how?

thanks very much!

Connected PPI to RS232 directly????

Its wired incorrectly

For something to get hot (burn) you need energy, there must be some electricity going where it should not go and so creating heat. The S7-200 port has 24V on pin 7 and 5V on pin 6, make sure you have no connections to those pins. Otherwise disconnect all cables going to the plug and then add them back one at a time until you find when the heat starts.

Bryan

thanks all
i wire the 24V- and PE