help me to connect a siemens s5-100 to a s7-200, are the any module cards out there that will do this for me? Can I do this without the intervention of a pc? Please help I am a plc virgin...

 

A small block in the s7-200 (as it is the faster machine) can be used to generate a clock signal at say 10hz, which goes low after 64 counts for say 500ms to signal the end of the data transmission. Copy this to a dc output this should be connected to an input on the S5. Use this clock signal to transfer data from a dc outputs to an inputs between your plcs this gives bidirectional communications of 8 bytes using only 3 inputs and 3 outputs.

I use this type of comms a lot to interface different types of plc - you can experiment with the speed and data length to suit your program.

 

With a CP521 there is a possibility to link serial with the S7-200 using the freeport on the S7-200 side.

In ID 41561 "S7-200 Communication possibilities" on the page by Siemens you can find the possibilities.

The CP521 have a RS232 port and the freeport is a RS485 port but with the cable that's mentioned in the ID 41561 you can fysicaly couple the two small ones. For the software you have to choose a protocol that's possible with both systems, ASCII is such one.

The page off Siemens:

http://www4.ad.siemens.de/WW/llisapi.dll?func=cslib.csinfo2&siteid=CSEUS

where you can find the ID and all other stuff.

I hope you have enough info to make the communication.

Best regards