thanks for the info. these are our older plc's that we used before our equipment came with S7, now we need to look at them and our cables are either gone or bad or in somebody's tool box.
ken, our plant is split into two divisions, on my side of the house we have the lower number 505 series, on the other side of the house they have the 565 and 575, i have never had to deal with them, that was the basis of that question.
thanks again.