Regards. Non-KONE guy here, so please keep that in mind. We're having a pesky issue with a KONE KCM831 with a V3F25 drive. It will run for up to an hour our two before the faults come in. It's a very hard abrupt stop, mid-flight. Fault string is as follows....0036, 0101,0126. Looking at the state of my inputs on the LCECPU when looking at the 0036 fault, I can see I have all required inputs, except 'Start Permit'. Thus far, I have replaced all relays in the start permit circuit, with no resolution. Now I'm thinking, maybe it's the motor tach that is giving me the issue??...as under fault description, it says to pull the motor tach. off the Drive. I did just that, midflight yo see if the same string of faults would be produce, and it was prerty close....I got a 0036, 0101, 0026, and 02..something when testing.

Any ideas guys? What do you think of my idea?