The rows are the causes (the initiators) and the columns are the effects (the final elements). A mark in a cell shows how a cause acts on an effect: X for a trip, T for a timed trip, P for a permissive and A for an alarm only. The component highlights the causes that are currently active and the effects that are currently tripped, and compares the two with the chart: an effect that should have tripped and did not, or that tripped without an active cause, is marked as a discrepancy in its column header.
Use Tab to focus the matrix. The arrow keys move between cells, Home and End move to the start and end of a row, Ctrl+Home and Ctrl+End move to the corners, and Enter opens a cell.
The marks property defines the letters used in the chart and which of them represent a trip. In this example H is a hold that prevents an effect from being reset; it is not a trip.