A component on the backplane of the MNL-800 controller was damaged during an electrical storm. What is it and which circuit is it a part of?

Issue

During an electrical storm, a component labeled MFC27 was damaged.  It is one of many similar components on the MNL-800 backplane or base circuit board.  What purpose does it serve and which circuit was it a part of?

Product Line

TAC I/A Series

Environment

MNL-800

Cause

High voltage spikes from an electrical storm.  Sample of MFC damage in image below.

Resolution

All the MFC components on the backplane are Multi-Function Ceramic (MFC) protectors.  They are designed to absorb high voltage introduced into the circuit to which they are a part of.  In particular, MFC27 protects universal input six (UI 6).   See a sample image of MFC damage below.

Although damaged, the backplane can still be used but that specific circuit won't have any further high-voltage protection.