While programming an inverter, if a constant is set outside an allowable limit, or an individual parameter setting is inappropriate based on another choice (changing the mode will make some parameters in appropriate for that new mode of control), an operator programming error will appear. These are called OPE's. The drive will not operate until this condition is cleared.

We do not discuss all available OPE codes as some should not happen based on how Milnor uses the inverter in our applications. If you see an OPE fault other than what is listed here on the web site, then contact Milnor Customer Support.