Motors On and Start - System Input

djf816

I am having difficulties using the motors on and start system input.  I have an external pushbutton to trigger this system input (logic done in my PLC).  It does come on but it takes 2 or 3 presses of the pushbutton to actually start the robot.  Does this signal need to be on for a set time or do I need to do something else in the robot settings?

lemster68

System inputs should be on for a minimum of 50ms.  Also check your event logs for anything that says that the system input is rejected.  Often times because motor off is still on or system input for stop at the same time.

SI-GT

Have you tried to separate the both signals in time?
I recognized a change in behaviour from RW 5.61 to RW6.0. Since RW6.0 you need a signal for motor on first and start/start at main has to be delayed for at least 500ms.

Fritz

Are you using only this one system input or is there going on some more actions same time?

There are some limitations what commands can be received simultaneously. Check system output called "System Input Busy" to check, if next command can be issued. From manual:

If Status has the value System Input Busy, that means the I/O signal is set when the system input mechanism is busy.For some actions the controller is busy for some time and cannot receive any commands, thus rejects any order. A new command must be sent when the controller is ready again. The status System Input Busy can be used to show if the incoming system input request will be rejected or not.

And also I suggest not to use single command "Motors on and start" but separately: first set "Motors On", then wait "Motors On State" in PLC. And only after that issue "Start" or "Start at Main" signal.
Such approach would allow better error handling and reporting on PLC side.