: Stores the last occurred system error code. It is highly useful for background logic macros designed to report errors to a master PLC.
: Stores status configurations for the Teach Pendant screen layouts and windows.
: Defines the maximum allowable speed for the specified motion group (where [x] represents the group number, usually [1] ).
: Contains configuration and diagnostic arrays for EtherNet/IP adapter and scanner connections.
: While most are internal or read-only (RO) for safety, many can be modified to customize operation. Key Categories : fanuc robot system variables pdf
123: GO[11]=($SCR_GRP[1].$MCH_POS_X*10) 124: GO[12]=($SCR_GRP[1].$MCH_POS_Y*10) 125: GO[13]=($SCR_GRP[1].$MCH_POS_Z*10) 126: GO[14]=($SCR_GRP[1].$MCH_POS_W*100) 127: GO[15]=($SCR_GRP[1].$MCH_POS_P*100) 128: GO[16]=($SCR_GRP[1].$MCH_POS_R*100)
These are among the most frequently utilized variables, allowing the logic to read the state of physical and virtual I/O.
To prevent the robot from being switched into Auto mode via the keyswitch, set the variable $SCR.$T2_LOCK_ENB to 1. This can be useful in maintenance or teaching setups where accidental mode switching could pose a safety risk.
: Tracks hardware states and the status of axis mastering procedures. Essential System Variables for Robot Operators : Stores the last occurred system error code
Several community-hosted resources provide access to FANUC system variables documentation:
In the FANUC robotics ecosystem, the controller (e.g., R-30iB, R-30iB Mate, R-30iC) relies on a vast database of pre-defined variables known as . Unlike user-defined variables (Registers, Position Registers, etc.), system variables are intrinsic to the operating system. They allow programmers and technicians to monitor the robot's status in real-time, modify system behavior without changing core logic, and integrate external peripherals.
: Controls global operational parameters like the speed override.
System variables in FANUC robots are permanently defined variables that are declared as part of the KAREL system software. These variables have names that consistently begin with a dollar sign ( $ ), making them instantly recognizable within programs and system interfaces. : Defines the maximum allowable speed for the
1. IF DI[10]=OFF THEN (Safety gate closed signal check) 2. UALM[3] (Gate open alarm) 3. ENDIF 4. 5. IF $SCR_GRP[1].$HOMED=FALSE THEN 6. UALM[4] (Robot not homed) 7. ENDIF
The Ultimate Guide to FANUC Robot System Variables: Configuration, Backup, and Troubleshooting
Toggles soft limit enforcement without requiring a hard stop cycle.
Many online resources are user-uploaded. Always verify information against official FANUC documentation when implementing system variable changes in production environments.
Keep a physical or digital log in the electrical cabinet noting which variables were changed, their original values, their new values, and the date of modification. Documenting and Exporting to PDF