Run permissive in Bypass and Run Contact
A Run permissive in Bypass (or just for a VFD) is typically a Normally open contact that requires a certain condition to be true in order to close and Permit the Bypass Motor Starter (or VFD) to close (Be placed in a Run condition) and cause the motor to Run, When in Bypass the Run Permissive may be controlled by a Normally Closed (NC) contact on the Contactor that provides Power to the VFD representing that the VFD cannot Run and that it is permissible to close the Bypass contactor. The permissive may have a number of conditions that enable or prevent the permissive contact from closing. These are design considerations, and Safety concerns, i.e. Emergency Stop contacts, etc.
A Run Contact can be Normally Open and closes when the VFD (variable frequency drive) is in a Run condition having received a run command, or a Normally Closed contact that opens when the VFD is in a Run condition having received a Run command.
A Run Contact can be Normally Open and closes when the VFD (variable frequency drive) is in a Run condition having received a run command, or a Normally Closed contact that opens when the VFD is in a Run condition having received a Run command.