Robot Startup Sequence from PLC Control

INTRODUCTION

The following is a guideline on how a Yaskawa robot should be started from an external device such as a PLC.  Similar logic would also apply to a manual push button control panel.  Please remember that the exact sequence can vary and will reflect differences from programmer to programmer and application to application. 

ADDITIONAL RESOURCES

Your Yaskawa robot features an internal concurrent I/O system (ladder logic) that maps all of the signals in use on your robot.  Having a good understanding of the concurrent I/O can be beneficial for you.  For even more information, please consult these articles:

I/O MAP

Before moving forward, you should ensure you have the correct I/O map for your robot.  The exact I/O map of your robot will vary.  Factors contributing to the different I/O maps are as follows:

• Pendant application software.  An arc welding robot will differentiate slightly when compared to a painting robot for the obvious reasons of signals related to the work that the robot is performing
  
  
• Hardware configuration.  Most robots have 1 dedicated I/O card plus a fieldbus board such as Ethernet/IP.  The exact configuration of your machine can and will influence your I/O map
  
  
• Country specific.  Countries such as Canada will have a different I/O map associated to Ethernet/IP as compared to the United States.  This is a localized country standard that has been in use for many generations of Yaskawa controllers.

In all cases, please consult your system documentation and/or your local Yaskawa tech support for help on identifying your current I/O map.

SIGNAL TYPES

	When the input signal is transitioning from a low state (e.g. 0) to a high state (e.g. 1)
	When the input signal is maintained at a high state (e.g. 1)

PRESTART CONSIDERATION

The teach pendant comes with a 3 position key switch.  TEACH, PLAY and REMOTE.  In order for the robot to accept signals from your PLC, it must be in the REMOTE position.

STARTUP SEQUENCE

SIGNAL DESCRIPTION	SIGNAL TYPE		CIO SIGNAL  ADDRESS
Remote mode confirmation	output		70025
Play mode confirmation	output		50054
Play mode selection	input		40041
Servo power confirmation	output		50073
Servo power selection	input		40045
Master job confirmation	output		50020
Master job selection	input		40070
Start confirmation (operating)	output		50070
External start	input		40044

The robot only requires each signal be momentarily sent to activate the desired feature (servo’s, running, etc…)  It does not need to be maintained and no harm will occur if you should do so.  Best practice is to remove the signal once you have received confirmation.  

In the example above, once the robot has been successfully started, all start-up logic is blocked from re-occurring.