please explain k,p bus -UR1/UR2, ER1/ER2,CR2

I would be glad if someone tells me diffrence between P Bus and K bus.how about UR1/UR2, ER1/ER2,CR2
is it usefull to know buses for configuration of s7-400?

tomkens

Lets see if I can help you out here with my limited knowledge of S7 400 racks.

The two types of backplane bus available are the P and K bus, from what I remember the P bus is for I/O updates and the K bus for communications updates. The P bus is the slowest and is also the only bus available on the S7 300 range.

The racks mentioned are as follows:-

UR1 - Universal rack, 18 slots wide, has both P and K bus
UR2 - Another universal rack, 9 slots wide, again has both P and K bus
ER1 - Expansion rack, 18 slots wide, only P bus available
ER2 - Expansion rack, 9 slots wide, only P bus available
CR2 - central rack, 18 slots wide but split into two segments, this can be used for operating two independent S7 400's, each with their own I/O etc, but both PLC's can communicate with each other via the K bus in the backplane.

There is one other rack that you didn't ask about, that is the CR3 rack, CR3 is very similar to the CR2 rack, but is usually used with S7 400H PLC's, it can also be used as an expansion rack.

tomkens said:

is it usefull to know buses for configuration of s7-400

Click to expand...

I don't think so.

Hope this helps you a little.

Paul

Great answer , 2 thumbs up!