J.P. Instruments EDM 760 Instrument Installation Manual - Manual (Page 2)

Installation manual for the EDM-760 Twin STC SA00729SE
Report No. 760
Temperature indicating system with Fuel Flow Date 7/20/99 Rev NC
Page 2 of 19
1) INSTALLING THE INDICATOR
Installation Should Be Done In Accordance With Advisory Circular AC43.13-1A
A steel template supplied with the installation kit is used as a guide for drilling two buttonholes in the instrument panel.
Align and Mount the Template into the instrument panel hole. First drilling a 0.125 hole. Remove the template and check
the instrument alignment, if OK re-drill with a 0.147 drill. The plastic buttons are removable by pulling off. The EDM-760
mounts in a standard 3.125" instrument hole. The instrument configures itself automatically for Twin 4 or 6 cylinder,
14/28 volt aircraft. The instrument is 7.5” deep less connectors and is 3.20 square behind the panel..
TO PREVENT DISPLAY DAMAGE IT IS ESSENTIAL THAT THE FOUR MOUNTING SCREWS NOT PENETRATE THE
INSTRUMENT MORE THAN .12 INCHES. DAMAGE OF THIS NATURE IS NOT COVERED UNDER WARRANTY.
2) EXHAUST GAS TEMPERATURE PROBE (EGT)
The Model M-111 Probe will fit any existing holes in the exhaust stack in any engine having the diameter of 1/8" to 1/4". If
no hole exists, it will require the drilling of a 1/8" diameter hole and ream to fit. It is important that each probe be mounted a
uniform distance from the exhaust stack flange. A nominal distance of 2 to 4 inches from the exhaust flange is
recommended. (See fig-2). If the recommended distance is impractical because of obstructions, slip joints or bends in
the exhaust system then position the probes a uniform distance from the flange as space permits. Do not mount probes in
slip joints. Be certain to locate all holes BEFORE drilling to ensure that nothing interferes with the probe, clamp, and clamp
screw or wire. Careful matching of probe position will provide best temperature readings.
Insert the probe in the exhaust or previously drilled hole (see fig-3) so that the tip of the probe is in the center of the
exhaust stream. Tighten the stainless steel clamp to a torque of 45 in/Lbs. Cut off the excess strap close to the screw.
3) TURBINE INLET TEMPERATURE PROBE (TIT)
The standard TIT probe P/N M-111-T with a special clamp is placed in the exhaust stack accumulator to a maximum depth
of 1/2 inch and approximately four (4) inches from the Turbine inlet if possible, on the wastgate side of the turbine. TIT will
appear as the seventh column “T “and the expression “1650 TIT” will be seen when the dot is in place over it.
4) USE ORIGINAL TIT BY PIGGY BACKING ORIGINAL
The EDM-760 input is compatible with the aircraft’s factory TIT and will not load the factory probe. Connect the EDM-760 TIT
wire to the same red/yellow leads on the factory probe. Check calibration by running up the engine and noting if there is and
difference between the factory reading and the EDM-760 reading. Note any difference and mark it down plus or minus. Then
Hold the two buttons in and Program/Rate - 4 will display. Again hold the two buttons in and TIT +0 / ADJ. will appear. Tap
the LF to subtract and hold to add. When the correct difference is displayed tap step to go to back to TIT reading. Reading
should be close to correct, repeat as required.
5) CYLINDER HEAD TEMPERATURE PROBE (CHT), BAYONET
The Bayonet probe 5050-T has the 3/8-24 boss as part of the probe and is screwed into the base of the cylinder
(See fig-2). The bayonet probe has a screwdriver slot to facilitate tightening.
NOTE: Required original equipment that has a Red Line may not be replaced by the EDM-760 TIT or CHT installation. This
includes but is not limited to all aircraft with adjustable cowl flaps and on aircraft with placards on the instrument panel
showing a climb air speed, for cooling, different from the best rate of climb air speed.
If a previously installed TIT, CHT or EGT is not required for certification (or STC modification), it may be replaced by the EDM
760.