J.P. Instruments » General Questions

General Questions

This is issued for probes used by the EDM’s. If an A&P asks for this ‘Certificate of Compliance’ after receiving a set of CHT probes as an example, we can fax them this ‘Certificate’. We will need the invoice number in order for JPI to do this.

Date in STC on the “FAA Approved JP Instruments Drawing List Report #100, etc.” does not match the date of the EDM-700/800 installation manual #103.

Report #100 is an INTERNAL document between JPI and FAA. Customer does not have nor need this document.

NO. And JPI has not interest in doing so. We deal with the FAA only.

For the EDM-700/800/760 and the FS-450/450M, these are all advisory equipment only – in other words – along for the ride. Therefore they are considered: ‘Airframe’ STC’s.

For the EDM-711 Primary and the EDM-900/930 Primary, these units replace the aircrafts gages and parts – oil pressure, fuel pressure, CHT gage and its probe, etc. Therefore their STC’s are considered an “Engine” STC.

The Remote Alarm Display (RAD) pulses at the same rate as the display error flash rate when an alarm is active. For EDM-700 it is two per second, 50 percent duty cycle. Similar for Slim-line.

For EDM-900/930, the RAD displays RPM & MAP without pulsing if no alarms are active.

No. Our policy clearly states: Urgent, read this before installing this kit If you are an FBO, inform your customer before installing kit. The JPI warranty found on the back of the “Pilots Operating Manual” clearly states that JPI will replace defective parts under warranty, but does NOT cover Labor to remove or install new parts. If you disagree with this warranty, take advantage JPI money back guarantee.

Here are some ballpark numbers: ( remember each aircraft is different.)

FS-450 – about 10 hrs

FS-450M for a twin – about 16 hours

EDM-700 EGT/CHT only, installation time is about 10 hours. For fuel flow an additional 5 to 10 hours (add one hour for each temp ‘Option’ installed).

EDM-800 installation requires about 25 hours.

For an EDM-760 it takes about 30 hours; add 6 -10 hours for fuel flow.

EDM-900/930 – around 40 hours. [ 50 to 60 hours with panel cut and Fuel Quanity procedure.]

* Times will vary with each aircraft. *

(1) Use steel fittings with the FXT‑201 or FXT‑231 fuel flow transducer. Do not use aluminum. **Note: Do not use teflon tape or thread sealant compound of any kind on fittings to the transducer.
(2) To prevent damage to the display it is essential that the four mounting screws not penetrate the instrument more than  1/8″,  0.120″ (3mm).  ** Note: Damage caused by screw penetration is not covered under warranty.
(3) Determine the locations of all holes before drilling to ensure that nothing interferes with the probe, clamp, clamp screw or wire.
(4) Provide service loops at the instrument. Thermocouple wire length is not critical. Trim to required length, allowing for service loops at the engine so that probes can be swapped with probes on adjacent cylinders for troubleshooting purposes.
(5) Power up and test the instrument before installing in the instrument panel.
(6) Dress all wires away from high temperature components such as exhaust stacks.
(7) Never splice thermocouple wire using copper wire. Use only K‑type thermocouple wire. Solder using zinc chloride flux such as Nokorode brand – rosin flux won’t work. ** Note: A better choice is to use good quality butt splices.
(8) Observe correct polarity on all probe wires. Connect like colors together (red to red, yellow to yellow).
(9) The most common cause of probe problems is poor terminal crimps. Crimp ring terminals with AMP part 45518 crimp tool or equivalent.
(10) The instrument must be grounded at the engine, not at the avionics ground.

(11) If a spark plug gasket probe is used, expect the CHT reading on that cylinder to be somewhat higher than on the cylinders with bayonet probes. At additional cost an adapter probe (bayonet or screw‑in) is available that permits the factory CHT probe and the JPI probe to be placed in the same bayonet location.

JPI uses K-type thermocouple wire.(Yellow and red color code)
GEM uses J-type (White and red color code)

EGT in cruise <200 HP 1350°F
EGT in cruise high performance 1550°F
DIF (EGT) fuel injected 70 – 90°F
DIF (EGT) carbureted 120 – 150°F
TIT 1600°F average
CHT 350 – 410°F
CLD (shock cooling) -40°/minute tightly cowled, -55°/minute Bonanza, -200°/minute helocopter.

  • EDM-700 14.5 oz. without fuel flow.
  • EDM-700 16.5 oz. with fuel flow, xducer 3 oz.
  • EDM-760 18 oz.
  • EDM-900/950 1.7 lbs.
  • EDM-930 2.7 lbs.
  • Classic Scanner 100 10.5 oz.
  • EGT probe M111 2.0 oz.
  • CHT probe 505 1.5 oz.
  • Wire harness 8 ft 14 oz.
  • Wire harness 20 ft 32 oz.
  • OAT and OIL T probes 1.5 oz

  • EDM-700   –  2.5 x 2.5 x 8″ with 2 1/4 bezel, incl connector.
  • EDM-760   –  3.25 x 3.25 x 8″ with 3 1/8 bezel. Incl connector.
  • Slim-line    –  2.0 x .950 x 3.5″ box (mounting ears 2 3/4 wide).
  • FS-450       –  2.5 x 2.5 x 2.3″ deep incl connector.
  • EDM-900   – 3.26″ deep (connectors recessed)- 4.52″ wide – 3.31″ high
  • EDM-930   –  3.3″ deep(add 2″ for connectors)    -5.584″ wide – 5.11″ high
  • VM-1000C –  1.91″ deep(add 2″ for connectors) -5.59″ wide – 6.13″ high

  • Instruments for three years.
  • Probes for one year.