Fanuc Keep Relay Parameters Exclusive [new]
: Switch the machine to MDI mode , go to the Setting screen, and change "Parameter Write" from 0 to 1 .
Understanding how operate is an essential skill for CNC machinists, maintenance technicians, and automation engineers. Keep relays (often denoted as K parameters ) act as the bridge between the CNC controller and the Programmable Machine Controller (PMC). Among the various types of keep relays, understanding mutually exclusive keep relay parameters is crucial.
FANUC CNC systems rely on Programmable Machine Control (PMC) to manage the interface between the CNC software and the physical machine tool. Within the PMC, Keep Relays (K-parameters) act as non-volatile internal switches. They allow field technicians and programmers to change machine behaviors, enable hidden options, or toggle specific safety logic without rewriting the underlying ladder program.
) are reserved for Fanuc system functions, such as enabling ladder editing or controlling how data is backed up to flash memory. fanuc keep relay parameters exclusive
Modifying turret rotation restrictions to allow faster tool changes, for example, changing a K17cap K 17
This article provides a deep dive into what keep relays are, why they are exclusive, and how to safely manage them. What are FANUC Keep Relays (K-Parameters)?
Ensure specific relay (keep-relay) parameters persistently remain enabled/unchanged and are not overwritten by automatic parameter loads, backups, or other user changes on FANUC CNC controls. : Switch the machine to MDI mode ,
Machine builders use these parameters to provide "exclusive" access to functions that might otherwise require complex PLC ladder modifications.
— Some exclusive K relays directly control emergency stop behavior or hardware interlocks. Changing them outside FANUC specifications can create hazardous conditions.
In FANUC's CNC systems, parameters are crucial as they define the operational characteristics of the machine. The "keep relay parameters exclusive" feature refers to a setting or function that allows certain parameters related to relay outputs to be preserved or kept unique, even during power cycles or system resets. This ensures that specific configurations or settings for relay outputs are maintained, providing consistency and reliability in the machine's operation. Among the various types of keep relays, understanding
Input the new binary value ( 0 or 1 ) and press the key.
Fanuc uses internal keep relays to manage communication profiles. For instance, specific bits in the K90+ range dictate whether the PMC treats specific I/O modules as standard digital signals, analog cards, or safety-related modules. Functional Safety / Dual Check Safety (DCS)
Press the right extension softkey ( > ) until you see (PMC Maintenance) or PMC . Press PMC MNT , then press the K-PARAM softkey.
Always consult your machine's original documentation or the OEM ladder diagram before changing Keep Relays, as they are specific to each machine builder and changing the wrong bit can disable critical safety features or machine functions. common K-relay addresses used by specific manufacturers like Haas or Mori Seiki?