External encoders and linear scales are provided by various companies. Certain service / maintenance controls can be done via Mitsubishi CNC unit, but not in full. In this article, we explained how to cancel external encoder or linear scale.
Service engineers can have difficulties during service e.g. A machine that makes a positioning error, various feedback alarms etc… Separation of the external encoder / linear scale system could sometimes be convenient.
Things to Know
- This process should not be performed remotely by the end user.
- MTB may have defined this procedure in a different way, always follow manufacturers manuals.
- Axis movements must be done slowly and carefully, otherwise accidents/unwanted results may occur.
How to Cancel?
- First, machine and NC is powered on. Conditions necessary to write parameters (opening the PARAM menu, entering the password if necessary, etc.)are fulfilled.
- The axes are then manually moved to a distance far from the workpiece by hand and in manual mode. If possible, remove the workpiece from the machine to avoid potential problems.
- The parameters are then backed up to avoid any mistakes you may make while changing parameters.
- Original values off #2217 – #2220 and #2225 are read out and noted once.
- #2217 bit 1-2-3-4 are set to 0.
- As you can see in the picture, which axis is to be canceled later, the value written in parameter #2220. #2219 is entered from the parameters of that axis. (In the picture X-axis is sampled.)
- For example, if the value of parameter #2225 is 4204, this value is changed to 2204.
7. The machine is switched off and the cable of the external feedback is removed via the drive.
8. The machine is turned on and service could be continued.
9. To re-enable the canceled encoder, machine is switched off, the cable is connected and the parameters are reset to their original values.