KUKA Error 1426 — VARIABLE STACK OVERFLOW
ErrorDisplayed as KSS01426 on KRC4 / KRC5 controllers
KUKA 1426 (“VARIABLE STACK OVERFLOW”): The stack depth for variables has been exceeded. First check: Modify the variable accordingly.
Updated 2026-09-09 · LogrobotLM reference
Cause
The stack depth for variables has been exceeded.
Effect
Stop via braking ramp. All active commands are inhibited.
Troubleshooting
Modify the variable accordingly. Acknowledge the message.
Related codes
Indicative field information — the robot manufacturer's manual and safety procedures always prevail. Never bypass a safety device; apply lockout/tagout (LOTO) before any physical intervention. How this reference is built →