J.P. Instruments EDM 900 User Manual

Pilot’s Guide

Engine Data Management

EDM-900

Primary

TSO/STC

Copyright 2011 J.P. Instruments, Inc.

All Rights Reserved

J.P. INSTRUMENTS INC.

Information: P. O. Box 7033

Huntington Beach, CA 92646

Factory: 3185 B Airway

Costa Mesa, CA 92626

[phone] Fax [phone]

www.jpinstruments.com

www.JPITech.com

www.buyJPI.com

Printed in the United States of America

Rev A

Last printed

For Your Safe Flight

Page 1

Table of Contents

Section-1	Getting Started	4
View Angle		4
Rotation		6
Fuel Flow Computer Basics (independent of fuel quantity)		6
Display Screen Basics		7
Horizontal Display Mode		7
Vertical Display Mode		8
Remote Annunciate Light Basics		8
RPM and MAP Display Basics		9
Linear Bar Graph Display Basics		9
Scanner® Information Area		10
LeanFind Basics		11
Section 2 -	Interpreting Data	12
Operation for each Phase of Flight		12
Typical Normal Measurements		14
Section 3 - Displays and Controls		17
Control Buttons		17
Scanner Displays		19
Additional Displays Hobbs, Revisions, and Alarm Limits		21
Dimming the Display		22
Section 4 -	Operating Modes	22
Automatic Mode		22
Manual Mode		23
Section 5 -	LeanFind	24
LeanFind Procedure—General Explanation		28
Expanded Leaning Procedures		31
Common Misapplications		32
Section 6 - Fuel Flow Operation		33
Fuel Management		33
Start Up Fuel		34
Resetting ‘USD’		35
Trip Mode (Accumulate Trip Totalizer)		35
Scanner Fuel Flow Display Select		35
Section 7 -	Alarms	36
Section 8 - Memory and Data Download		37
Downloading Data from the EDM		37
Transferring data from the USB Flash Drive to a PC		38
Section 9 - First Time Setup and Customization		38
Section 10 -	Adjusting Manifold Pressure & %HP	41
Adjusting the HP Constant for Rich of Peak Operation		41
Adjusting the MAP		41
Adjusting the HP Value		42
Section 11 -	Programming the Fuel Flow	42
Page 2	Engine Data Management

Fuel Flow K factor		43
Programming Trip Mode		45
Setting the GPS Com Format		45
Troubleshooting the EDM		47
Diagnostic Testing on Startup and During Flight		47
Diagnostic Messages		47
Section 12 -	Appendices	48
Shock Cooling (CLD)		48
List of ALL messages in EDM-900		49
Navigation Data Formats		50
Navigation Data Ports for GPS Comm		50
Interface connections to selected GPS models		50
Section 13 -	Technical Support	51

For Your Safe Flight

Page 3

Section-1

Getting Started

This is a summary of basic operation. Detailed descriptions of all operations appear later in this Pilot’s Guide.

EDM-900 primary instrument has preset alarm limits and cautionary ranges per the POH (user cannot change them) typically for the following measurements of: oil temperature, oil pressure, fuel pressure, fuel quantity, cylinder head temperature, turbine inlet temperature, manifold pressure, and RPM.

Note: Fuel quantity gauges must be calibrated to the aircraft and will not be functional until the fuel calibration process has been performed.

View Angle

The best view angle for the pilot is in the horizontal mode with the buttons on the bottom. The best Portrait mode is with the buttons on the right.

View angles are per the table below:

	Horizontal	Left	65 Degrees
Viewing
		Right	65 Degrees
angle
	Vertical	Left	60 Degrees
		Right	50 Degrees

Page 4

Engine Data Management

List of abbreviations and acronyms

	Gauge Function			Message Area
				Alarm Abbreviation
	Primary			Primary
	Engine rotational speed		RPM xxxx
	Engine Manifold Pressure		MAP xx.x in hg
	Engine Cylinder Head Temp		CHT2 xxx oF
	Engine Oil Temperature			O-T xxx oF
	Engine Oil Pressure		O-P xxx oF
	Fuel Pressure		F-P xx PSI
	Fuel Flow to engine			F-F xx.x GPH
	Comp. Discharge Temp.		CDT xxx oF
	Turbine inlet Temp. Left side		TIT-L xxxx oF
	Turbine Inlet Temp. Right side		TIT-R xxxx oF
	Single Turbine Inlet Temp.		TIT xxxx oF
	Non-Primary		Non-Primary
	Exhaust Gas Temp.		EGT2 xxxx oF
	Shock Cooling of CHT		CLD xx o/MIN
	Differential Temp. of EGT		DIF xx oF
	Bus Voltage		Volts xx.x
	Amperage Load		AMPS xx
	Outside Air Temp.		OAT xx oF
	Estimated Time to Empty		Est. T to E xx:xx H:M
	Fuel used to date		USED xx.x GAL
	Estimated Remaining fuel		Est. REM xx GAL
	Estimated Fuel required to Waypoint		Est. WP REQ xx GAL
	Estimated Fuel Remaining at			Est. WP RES xx GAL
	Waypoint
	Nautical Miles per Gallon		ECON xx.x MPG
	Brightness, Dim control		DIM/BRT

For Your Safe Flight

Page 5

Rotation

Holding the step button in for 5 seconds, with the engine OFF, will produce the gray arrow. This arrow can be rotated to a new up position by tapping the LF button and then the STEP button. If for some reason you chose the one bad angle (Landscape looking up from the buttons), return the instrument to JPI and JPI will rotate the screen.

Fuel Flow Computer Basics (independent of fuel quantity)

The fuel flow computer tracks the fuel flowing to the engine and computes various values based on this. At installation, then each time you refuel the aircraft, you must inform the EDM about how much useable fuel is onboard. This is done via the REFUEL function.

See page 33 for detailed information

Control Button Basics

Four operating buttons control all functions of the EDM. These buttons change labels depending on the current state of the EDM.

Page 6	Engine Data Management

Display Screen Basics

The display screen is arranged into three sections. The top left is the MAP and RPM section. The bottom left is the Scanner® section or message area. On the right side are the horizontal primary strip gauges. Non-Primary gauges have a digital read out only. The instrument ranges and alarm limits are configured to match those of your aircraft POH when the EDM is set up as a Primary instrument. TIT column is to the right of the last EGT/CHT when applicable.

Horizontal Display Mode

For Your Safe Flight

Page 7

Vertical Display Mode

Remote Annunciate Light Basics

The Remote Annunciator Light ‘RAL’ provides notification that an alarm is present in the display, for all Primary gauges. Upon power up, the RAL shows Red and yellow indicating it is functional. Before each flight, confirm that it is functional. Non-functioning RAL must be repaired before flight.

Remote Annunciator Light (RAL)

Page 8

Engine Data Management

Horizontal mode

Vertical mode

RPM and MAP Display Basics

In the vertical mode to the right and the Horizontal mode above MAP (Manifold Pressure) and RPM (Revolutions per Minute) are shown. Operations exceeding red line cause the digital value to turn red or yellow with the RAL coming on and a digital value in the Scanner message area.

Linear Bar Graph Display Basics

The Bar Graphs section contains dedicated bar graphs with digital display. An example is shown here. Pointers move horizontal left to right showing value changes and digital readouts turn red

when primary exceedances occur. Non primary functions flash white.

Horizontal mode	Vertical mode
For Your Safe Flight	Page 9

Scanner® Information Area

The Scanner® Information Area provides expanded information in the form of alpha-numeric messages, parameters and calculations. In Auto-Scan, parameters will ‘scan by’ once every 4 seconds (default). This rate can be changed in Pilot Programming Mode. Tap the STEP button for ‘Manual’ selection of any parameter. Parameters for the installed options will be displayed. To start the automatic scan tap LF and then STEP.

	DISPLAY	PARAMETER	DESCRIPTION
	EGT 1436 CHT 382	EGT/CHT	Shows successive pairs of EGT &
			CHT per STEP tap.
	TIT 1580 oF	TIT	Single Turbine Inlet Temp.
	TIT-L and -R 1490	TIT-L, TIT -R	Two Turbine Inlet Temp. Left and
	oF		Right engine side
	Oil-T 204 oF	OIL TEMP	Oil temperature in degrees F
	Oil-P 64 PSI	OIL PRES	Oil pressure in psi
	F-P16 PSI	FUEL PRES.	Fuel pressure in psi
	F-F 2.7GPH	FUEL FLOW	Fuel flow in GPH
	CLD 75 oF	SHOCK	CHT cooling rate (deg/min)
		COOL
	VOLTS 13.9	BATTERY	Battery/Bus voltage
	AMPS -6	Amperage	Set up per the specific aircaraft
	OAT 23 oF	OAT	Outside air temperature F or C
	DIF 40 oF	DIF	Hottest minus coldest EGT
	CRB 56 oF	CRB	Carburetor Air Temp (only allowed if
			IAT not present)
	CDT 145 oF	CDT	Compressor Discharge Temp (only
			allowed if CRB not present)
	IAT 105 oF	IAT	Induction Air Temp
		FUEL	Calculated fuel remaining on board
	Est. REM 68.0 GAL		based on what the pilot put in as
		REMAINING
			maximum.
		FUEL	Calculated fuel required to reach
	WP REQ 12.7 GAL		waypoint or destination (GPS
		REQUIRED
			interface must be corrected)
	Est. WP REM 63 GAL	FUEL	Calculated fuel reserve at waypoint
		RESERVE	(GPS interface must be correct)
		Nautical	Calculated fuel miles per units
	ECON 9.8 MPG	MILES PER
			(GPS interface required)
		GALLON
		Estimated	Calculated time remaining to fuel
	EST. T to E 04:32	Time to	exhaustion in Hours and Minutes at
	H:M	Empty	present power.
	GPH 15.0 GPH	FUEL FLOW	Actual fuel flow rate in Gallons per
		RATE	hour
	USD 7.2 GAL	FUEL USED	Actual fuel used by the engine
	FUEL-P 64 PSI	FUEL PRES	Fuel pressure in PSI

Page 10 Engine Data Management

LeanFind Basics

Simply pre-lean, tap the LF button (Lean Find) and begin leaning. The EDM will assist you in finding the first cylinder to peak. This example is for Rich of Peak, ROP. See page 24 for a more detailed description of leaning. Press LOP to exit the ROP mode and enter the LOP mode.

1.Establish cruise at approximately 65 to 75% power and pre-lean the mixture to 50°F estimated rich of peak EGT on any cylinder.

2.Wait about 30 seconds, then tap the LF button.

3.Begin leaning the mixture smoothly without stopping. Turn a vernier about ¼ turn per second; retract a non-vernier or quadrant lever so that EGT rises about 10°F per second.

4.Stop leaning when you see LEANEST for two seconds, followed by— for example— EGT1449 FF14.7 The left number is the current temperature of the first EGT to peak and the right number is the current fuel flow.

5.Now tap the PEAK button to display the EGT difference from peak which is very useful for setting desired degrees below peak.

6.Slowly enrich the mixture noting that the EGT difference diminishes as EGT climbs back to peak, followed by it going minus again. Stop enriching at the desired EGT difference (such as ‘EGT -75’).

7.You can also see what the peak EGT was by holding the PEAK button.

8.Tap STEP to exit the Lean Find Mode.

For Your Safe Flight

Page 11

Section 2 - Interpreting Data

Operation for each Phase of Flight

(Worth adding to your run-up checklist)

Engine

Run-Up

Take-Off,

Climb, and

Full

Throttle

Operations

Suggested setup:

Set engine to run-up RPM

Normalize view:

Manual mode

Verify:

Uniform rise of about 50°F in all EGTs in single magneto operation.

Uniform rise of EGTs with application of the mixture control.

Be alert for:

unusually low voltage (less than nominal battery voltage)

cold OIL and normal oil pressure

abnormally high CHT

Large drop in EGT on one cylinder in single magneto operation—may be fouled spark plug.

Suggested setup:

Standard view

Automatic mode

Verify:

EGTs and CHTs consistent with past climbs. EGTs should be in the 1100 to 1300°F range (100° to 300°F cooler than cruise) due to fuel cooling.

Be alert for:

High EGT in one cylinder, 300°F above the others may indicate plugged injector or leaking manifold gasket on a carbureted engine. At high density altitude an overly rich mixture can significantly reduce engine power.

If all EGT columns go off scale to the top of the column, be sure you are not in Normalize view, as indicated by the symbol NRM above the Scanner® section.

Page 12

Engine Data Management

After the engine is warmed up, use LeanFind to lean the mixture.

Cruise

Suggested setup:

Normalize view

Automatic mode

Be alert for:

Uneven EGTs (injected engines). Make fine adjustments to throttle, then RPM, then mixture to level the display columns.

Abnormal patterns of EGTs and CHT. (see Engine Diagnosis Chart on page 15).

Suggested setup:

Standard view

Manual mode

Descent	Be alert for:
	CLD: shock cooling alarm is set to -60°F. Average
	cool rates of -40°F/minute to -50°F/minute are normal,
	depending on the engine size.

For Your Safe Flight

Page 13

Typical Normal Measurements

The following chart lists typical normal measurement values that you will observe for most general aircraft engines. Your particular engine’s ranges may not fall within these values.

Measurement

Normal range

Comments

EGTs in Cruise

EGT span (DIF)

TIT

CHTs

CHT span

OIL T

	1350°F		under 200 HP engines
	1550°F		high performance engines
			(EGT should drop 200°F when
			full throttle is applied)
	70 to 90°F		fuel injected engines
	120 to 150°F		carbureted engines
	1600°F average		100° higher than EGT
	350°F (OAT 60°F)		normally aspirated engines
	410°F		Turbocharged engines
	50 to 70°F		100° with gasket probes
	200°F		oil cooler thermostat typically
			opens at 180°F

OIL P

FUEL P (injected)

FUEL P (carbureted)

Shock cooling*

30 to 60 psi		varies with aircraft type
14 to 18 psi		varies with aircraft type
0.5 to 8 psi
-40°/minute		tightly cowled engines
-55°/minute		Bonanza
-200°/minute		helicopter

*Maintain a cooling rate magnitude of less than -50°/minute. You will find that the cylinder with the greatest shock cooling may shift from front cylinders (during climb out) to the rear cylinders (during descent ).

Page 14

Engine Data Management

Engine Diagnosis Chart

The following chart will help you diagnose engine problems in your aircraft.

Display

Symptom

Probable

Recommende

Cause

d Action

TIT ~100°

This is normal

higher than

EGTs

75° to 100°

Spark plug not

Enrich mixture to

EGT rise for

firing due to fouling,

return EGT to

one cylinder

faulty plug, wire or

normal. Have

during flight

distributor.

plugs checked.

EGT Increase

Improper timing:

Check EGT for

or decrease

high EGT

each magneto to

after ignition

retarded ignition;

determine any

maintenance

low EGT

uneven timing.

advanced ignition.

Loss of EGT

Stuck valve. Other

Have valve train

for one

cylinders are okay.

checked.

cylinder.

Engine rough

Loss of EGT

Failed probe

Swap probes to

for one

or

determine if probe

cylinder; no

failed wire harness.

or wire harness is

digital EGT

bad.

Decrease in

Intake valve not

Have valve lifter or

EGT for one

opening fully; faulty

rocker arm

cylinder

valve lifter.

checked.

Increase in

Low compression

Check

DIF at low

(blow by) in

compression.

RPM

cylinder

EGT and

Normal for

Check injectors

CHT not

carbureted

and plugs.

uniform

engines. Dirty fuel

injectors or fouled

plugs.

Decrease in

Decrease in airflow

Check for change

EGT for all

into the induction

in manifold

cylinders

system. Carb or

pressure.

induction ice.

For Your Safe Flight

Page 15

Display

Symptom

Probable

Recommended

Cause

Action

Slow rise in

Burned exhaust

Have compression

EGT. Low

valve. CHT is low

checked.

CHT

due to low power

output.

High CHT on

Obstruction under

Check for improper

cylinders on

cowling.

installed baffling,

one side of

cowl flap

engine

misalignment or bird

nests.

Rapid rise in

Detonation.

Reduce power.

CHT of one

cylinder

Sudden off

Pre-ignition

Full rich and reduce

scale rise for

power.

any or all

Normalize view

Change to Standard

cylinders

view

or failed probe

Check probe

(no picture)

Loss of peak

Poor ignition or

Have magneto

EGT

vapor in fuel

tested.

injection system.

(no picture)

Decrease in

Detonation.

Enrich mixture,

peak or flat

Usually the result

reduce power and

EGT

of 80 Octane fuel

relean mixture.

response to

in 100 Octane

Repeat to find power

leaning

engine.

setting where normal

process

peak is obtained or

run rich.

Below 10,000

Weak or defective

Apply booster pump.

ft. full throttle

mechanical fuel

If EGTs drop,

causes EGTs

pump.

replace fuel pump.

to rise

CHT more

Leaking exhaust

Look for white

than 500°,

gasket blowing on

powder around

EGT normal.

CHT probe.

cylinder to determine

Adjacent EGT

leak area.

may be low

Page 16

Engine Data Management

Section 3 - Displays and Controls

The EDM monitors engine temperatures, pressures and voltages, assists in adjusting the fuel/air mixture, and helps diagnose engine malfunctions. There are multiple components of the user interface:

Four front panel operating buttons below the bottom of the display.

RPM and MAP display in the upper left corner of the display

Scanner analog display including cylinder number and index square in the lower left corner of the display

Scanner digital display for numeric readouts and messages at the bottom left

Bar graph displays on the right half of the display

Control Buttons

Four operating buttons control all functions of the EDM. These buttons may change labels depending on the current operating mode of the EDM. The term tap is used to denote pressing a button momentarily. The term hold is used to denote pressing and holding a button for five seconds or longer. Button layout is shown below:

1st Button

In the Automatic mode, tapping the STEP button stops Scanner autosequencing and changes to Manual mode. Each tap of the STEP button then displays the next measurement in the sequence. Holding the STEP button sequences in reverse order.

In the LeanFind mode tapping the EXIT button will terminate the LeanFind mode and change to the Automatic mode.

In the Program mode tapping the NEXT button will advance to the next item.

2nd Button

In Automatic or Manual modes, tapping the LF button will activate the LeanFind mode.

For Your Safe Flight

Page 17