J.P. Instruments EDM 760 Flight Manual Supplement - Manual (Page 3)

J.P.INSTRUMENTS Airplane Flight Manual Supplement
PO BOX 7033 Document No. 760-
1
HUNTINGTON BEACH CA 92646
Rev NC
Page 3 of 4
I GENERAL
The EDM-760 twin temperature indicator displays temperature digitally and in analog format for both
Left and Right engines simultaneously. The EGT as displayed is based on probes located near the
exhaust outlet for each cylinder and the TIT probe, if installed, in the turbo charger inlet. Before each
flight during the run-up the pilot should verify that the left engine is displayed on the left display and the
right engine on the right. . These probes are not necessarily collocated with the primary probes
therefore, EDM-760 may not indicate the same as the aircraft primary instruments. The analog display is
an electronic bar graph (vertical columns, one per cylinder) of EGT & TIT temperatures presented as a
percentage of TIT. Below the vertical columns the specific value for EGT and CHT are displayed
digitally. The dot over the column indicates which cylinder's digital information is presently displayed.
The missing bars at the base of the columns indicates the hottest and coldest Cylinder Head temperature
trend . Within a four bar range at the base of the column a trend is formed showing the hottest and the
coldest cylinder with respect to the others. Depressing the LF and STEP button simultaneously brings
up the adjustable Scan Rate, OAT in
o F or o C. Depress the LF button until the desired scan time is
reached. Exit by Depressing STEP.
If the EDM-760 buttons are not depressed for 10 minute the system will start scanning automatically.
Depressing the STEP button will stop the automatic scan and index through all the functions available.
During constant power cruise, if the LF button is depressed for five seconds the bar graph will level at
mid scale and the letter “N” (normalize) will illuminate. The leveled bars represent the peaks of each
column. Each bar represents 10
o F and now acts as an EGT & TIT trend monitor, quickly showing an
increase or decrease in temperature. Depress again to return to normal illuminating the “P”(percentage);
nothing else is affected. With the fuel flow option there is a three position toggle switch. The positions
are: 1) EGT, digital and Bargraph display of temperatures, 2) FF, digital display of GPH, REM and
USED Fuel. Temperature Bargraph remains. 3) Both , cycles through everything installed. The data
port output, sends RS232 serial data every 6 sec.
Options of Fuel Flow, TIT, OAT, IAT (induction air temp. Carb temp.), OIL, BAT (voltage) are only
displayed digitally with headlines after the number, as "230 OIL" or “14 GPH”. A large value (50 +) of
"CLD" indicates shock cooling usually associated with rapid descents at low power. Optional functions
not installed will not display.
Alarm limits set for
this instrument if
different from JPI
limits.
CHT__________
OIL__________
TIT__________
DIF__________
CLD__________
BAT__________
TECH_________
DATE_________
EDM-760
FAA APPROVED August 31 1999
LeanFind
STEP
Switch
DATA
Digital
Temperature
Analog
Temperatures EGT
1 thru 6 Percent
of 1650 F