Cause : Option Card Fault at Option Port CN5-C comes when same type of option card is currently connected or n option card of the same type is already installed in option port CN5-A or CN5-B.

1. Except for PG options, only one of each option card type can only be installed simultaneously. Make sure only one type of option card is connected.
2. Install a communication option, a digital input option, or an analog input option. More than one of the same type of card cannot be installed simultaneously.
3. Three PG option boards are installed- A maximum of two PG option boards can be used simultaneously. Remove the PG option board installed into option port CN5-A.