J.P. Instruments EDM 740 Pilots Guide - Manual (Page 9)

For Your Safe Flight Page 9
The following is a description of various display areas. Numbers in
circles refer to features in the above diagram.
1
Normalize View and Percentage View
 Percentage View: when the EGT normalize indicator ‘NRM’ is
not lit, the columns indicate percent of EGT red line. Each
column is composed of a stack of segments. A maximum height
column (all segments lit) depicts 100 %, or more, of red line and
a one segment-high column depicts 50 % of red line. For
example, if the red line is 1650°F, a maximum height column
represents 1650°F and a one segment-high column represents
half that value, or 825°F. The Percentage View permits
comparison of EGTs across all cylinders. Hotter cylinders
display higher columns than cooler cylinders.
 Normalize View: when the EGT normalize indicator ‘NRM’ is
lit, the EGT columns are displayed normalized. When you
activate Normalize View, all column peaks are set to the same
half-height level for trend analysis. Any changes are shown as an
increase or decrease in column height. A one-segment change
in column height represents a 10°F change. The Normalize
view permits rapid visualization of EGT trends, rather than a
percentage of red line. You should use normalize in level cruise
and run-up.
To toggle between Percentage View and Normalize View, hold the
LF button until the ‘NRM’ indicator either comes on or goes off.
Selecting the Normalize view does not affect the digital display nor alter
the parameter sequence. The CHT display—described later—is not
affected by either Normalize or Percentage view.
You may select the Normalize view in either the Manual or Automatic
modes, but not during Lean Find mode. Normalize view is most helpful
for engine trend monitoring of each cylinder’s operation. For example
using the Normalize view during engine run-up, a fouled spark plug will
appear as a higher column.
TIP: A common misapplication is to be in the Normalize view and then
change your power setting. This can cause all columns to go off scale,
high or low, giving you the impression there is a problem. Turn off
‘NRM’ (return to Percentage view) before adding or reducing power and
when beginning your descent.