Denford Software & Machines

Hi all!

I encounter a Z-axis problem with my 1985 ORAC and the situation is this... Both CD20 drives are running fine as long as they are inserted into x_axis rack socket. But if i insert a drive into Z-axis drive socket (first drive module from left to right) the green and the first top red leds of that drive are iluminated.
Now Pressing the Z-axis jog button turns off the green led and the top red led remains on and of course the motor refuses to spin. When i insert any of the two cd20 drives into the z-axis socket the x-motor runs perfectly.
I have to mention though that i am doing all this on the bench where the boards are interconnected just like they were on the machine. So, no limit switches are connected into the circuit.
This looks to be a controler problem to me as the data input part of the keyboard is not responding when pressing some of these keys but, i am not sure.
Will you pls help?

Thank you all!

Well, things came back to normal after replacing the shorted stepper.
So this goes for anyone interested...when green and top-red leds are illuminated at the same time on a CD20 Digiplan drive, this is simply a warning that the stepper motor connected to this drive has a short or maybe inapropriate coil interconnection caused by a careless somebody like myself..

cheers