J.P. Instruments EDM 930 User Manual

Pilot’s Guide

Engine Data Management

EDM-930

Primary

TSO

Copyright 2010 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
Printed in the United States of America	Rev I 10-12
Last printed 5/14/2013 9:17:00 AM

Table of Contents

Section 1 -	Getting Started	1
Display View Angle		2
List of abbreviations and acronyms		3
Fuel Flow Computer Basics		3
Control Button Basics		4
Display Screen Basics		4
Remote Auxiliary Display Basics		5
RPM and MAP Display Basics		5
Linear Bar Graph Display Basics		5
Scanner® Display Basics		6
LeanFind Basics		6
Section 2 -	Interpreting Data	7
Operation for each Phase of Flight		7
Typical Normal Measurements		9
Section 3 -	Displays and Controls	12
Control Buttons		12
RPM and MAP Displays		14
Scanner Displays		14
Remote Auxiliary Display		17
Hobbs Display		17
Dimming the Display		17
Section 4 -	Operating Modes	18
Automatic Mode		18
Manual Mode		19
Section 5 -	LeanFind	20
LeanFind Procedure—General Explanation		24
Expanded Leaning Procedures		28
Section 6 -	Fuel Flow Operation	29
Fuel Management		29
Start Up Fuel		30
Resetting ‘USD’		32
Resetting ‘USD’		33
Resetting ‘USD’		34
Trip Mode (Accumulate Trip Totalizer)		34
Scanner Fuel Flow Display Select		34
Section 7 -	Alarms	35
Non-primary Alarm Priority		35
Section 8 -	Memory and Data Download	36
Downloading Data from the EDM		37
Transferring data from the USB Flash Drive to a PC		37

Section 9 -	First Time Setup and Customization	38
Pilot Programming Mode		40
Adjusting the HP Constant for Rich of Peak Operation		42
Adjusting the MAP		42
Adjusting the HP Value		43
Fuel Flow K factor		43
Programming Trip Mode		45
Setting the GPS Com Format		46
Section 10 -	Custom Key Card	46
Section 11 -	Setting Fuel Calibration Points	47

Getting Started…Collecting Fuel Level Calibration Data using the EDM as a

meter.

48

After you have collected your data…Entering / Editing Fuel Level Calibration

Data		49
Troubleshooting the EDM		52
Troubleshooting the EDM		53
Diagnostic Testing on Startup and During Flight		53
Diagnostic Messages		54
Section 12 -	Appendices	56
TSO-only differences from Primary Instruments		56
Shock Cooling		57
Rear Apron Connector Locations		58
Connector pin assignments		58
Connector pin assignments		59
Navigation Data Formats		60
Navigation Data Ports for GPS Comm		60
Interface connections to selected GPS models		60
Section 13 -	Technical Support	61
Index		62
QUICK REFERENCE		66

EDM-930 SYSTEM DISPLAYS

EDM-930 Main display

Remote Auxiliary Display

(RAD)

Product Features

Hands-free, automatic scanning

LeanFind finds the first and last cylinder to peak with true peak detect—eliminates false peaks

Displays both leaned temperature below peak and peak

Battery voltage with alarm

Amperes (load or charge/discharge meter)

Programmable alarm limits

Exhaust Gas Temperatures (EGTs) to stable 1°F resolution

DIF low to high EGT with alarm

Shock cooling monitored on every cylinder

Fast response probes

Non-volatile long term memory

Records and stores data up to 30 hours

Post-flight data retrieval

Data retrieval software

Oil pressure

Oil temperature

Turbine inlet temperature, if applicable (optional)

Outside air temperature

Compressor discharge temperature (optional)

Carburetor temperature or induction temperature (optional)

Fuel pressure, if applicable

Fuel level Voltage, Resistive or Capacitive (frequency)

Fuel Flow

Solid-state rotor fuel flow transducer

Fuel quantity in gallons, kilograms, liters, or pounds

Low fuel quantity alarm

Low fuel time alarm

GPS interface

Instantaneous fuel flow rate

Total amount of fuel consumed

Total fuel remaining

Time to empty at the current fuel flow rate

RPM and manifold pressure

Automatically calculates percent horsepower

Hobbs® timer

Remote Auxiliary Display (RAD)

Section 1 - Getting Started

Important Note!

You must have the remote auxiliary display—RAD— installed on the instrument panel of your aircraft. This is required for FAA certification of the EDM-930 as a primary instrument. Upon start up, the RAD displays the make and model of you aircraft, which must be verified before you can rely on the EDM-930 for use as the primary engine instrument cluster. The RAD also will continuously notify you of any alarm conditions, regardless of whether you have cleared them on the EDM-930 display.

This is not an option!

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

EDM-930 primary instruments have preset alarm limits and cautionary ranges (user cannot change them) typically for the following measurements: oil temperature, oil pressure, fuel pressure, fuel quantity, cylinder head temperature, turbine inlet temperature, manifold pressure, and RPM. Your EDM-930 contains a custom Key Card. For Primary configurations, the Key Card activates the primary engine instrument abilities of your engine monitor.

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

Display 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	Up	50 Degrees
		Down	60 Degrees

For Your Safe Flight

Page 2

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 Waypoint		Est. WP RES xx GAL
	Nautical Miles per Gallon		ECON xx.x MPG
	Brightness, Dim control		DIM/BRT

Fuel Flow

Compute

r Basics

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. There are three ‘Quickset’ ways to do this:

1.Main 74.0 GAL: MAIN tanks are filled (no other fuel onboard).

2.Main + Aux 94.0 GAL: MAIN +AUX tanks are filled.

For Your Safe Flight

Page 3

3. Adjust? 0.0 GAL: Partial fuel added to existing quantity.

See page 29 for expanded information on the refueling process.

Control Button Basics

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

Display Screen Basics

The display screen is arranged into three sections. The top left is the RPM and MAP section. The bottom left is the Scanner® section. And the right side is the Linear Bar Graphs section. The instrument ranges and alarm limits are configured to match those of your aircraft when the EDM is set up as a Primary instrument.

For Your Safe Flight

Page 4

Remote Auxiliary Display Basics

The Remote Alarm Display ‘RAD’ provides alarm display, RPM and MAP, and is located directly in front of the pilot. Upon power up, the RAD shows the Aircraft model, engine type and declares instrument status: ‘Primary’ (if applicable). Before each flight, confirm that it matches your aircraft requirements.

RPM and MAP Display Basics

The upper half shows the RPM (Revolutions per Minute) and the lower half shows the MAP (Manifold Pressure). Operations exceeding red line cause the digital value to turn red.

Percent horsepower is displayed digitally below and to the left of the MAP arc.

Linear Bar Graph Display Basics

The Bar Graphs section contains nine dedicated bar graphs with digital display organized in a three by three matrix. An example is shown here. Pointers move up and down in response to value changes and digital readouts turn red when exceedances occur.

Note: functions displayed in this example may differ from your EDM.

For Your Safe Flight

Page 5

Scanner® Display Basics

The EDM Scanner section is located in the lower left area of the screen. It consists of a graphical display of EGT and CHT (and TIT if so equipped) and a digital display that automatically scans the various parameters. You can select Manual Mode by tapping STEP to lock onto the parameter of interest. To return to Automatic scan mode, tap LF followed by tapping

STEP.

LeanFind Basics

Simply pre-lean, then 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. See page 20 for a more detailed description of leaning.

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— EGT1520 FF13.8. 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. Note: The value for EGT ROP will be a negative value which means you’ve gone lean of peak by the time you stopped leaning the mixture.

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

Note: Please refer to the engine manufacturer’s operating guide for

For Your Safe Flight

Page 6

the correct value for EGT difference rich of peak operation at 75% and 65%

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

8.Tap STEP to exit the Lean Find Mode.

Section 2 - Interpreting Data

Operation for each Phase of Flight

(worth adding to your run-up checklist)

Engine

Run-Up

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.

For Your Safe Flight

Page 7

		Suggested setup:
			Standard view
	Take-Off,		Automatic mode
	Climb, and	Verify:	EGTs and CHTs consistent with past climbs. EGTs
	Full
	Throttle		should be in the 1100 to 1300°F range (100° to 300°F
			cooler than cruise) due to fuel cooling.
	Operations
		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.
		After the engine is warmed up, use LeanFind to lean the
	Cruise	mixture.
		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 10).

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 8

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

high performance engines

1550°F

(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

Turbocharged engines

410°F

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 ).

For Your Safe Flight

Page 9

Engine Diagnosis Chart

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

Display

Symptom

Probable Cause

Recommended

Action

TIT ~100°

This is normal

higher than

EGTs

75° to 100°

Spark plug not firing

Enrich mixture to

EGT rise for

due to fouling, faulty

return EGT to

one cylinder

plug, wire or

normal. Have plugs

during flight

distributor.

checked.

EGT Increase

Improper timing:

Check EGT for each

or decrease

high EGT retarded

magneto to

after ignition

ignition; low EGT

determine any

maintenance

advanced ignition.

uneven timing.

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 checked.

cylinder

valve lifter.

Increase in DIF

Low compression

Check compression.

at low RPM

(blow by) in cylinder

EGT and CHT

Normal for

Check injectors and

not uniform

carbureted engines.

plugs.

Dirty fuel injectors or

fouled plugs.

Decrease in

Decrease in airflow

Check for change in

EGT for all

into the induction

manifold pressure.

cylinders

system. Carb or

induction ice.

For Your Safe Flight

Page 10

Display

Symptom

Probable Cause

Recommended

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

power.

scale rise for

Normalize view

Change to Standard

any or all

cylinders

view

or failed probe

Check probe

(no picture)

Loss of peak

Poor ignition or

Have magneto tested.

EGT

vapor in fuel

injection system.

(no picture)

Decrease in

Detonation. Usually

Enrich mixture,

peak or flat

the result of 80

reduce power and

EGT response

Octane fuel in 100

relean mixture.

to leaning

Octane engine.

Repeat to find power

process

setting where normal

peak is obtained or

run rich.

Below 10,000

Weak or defective

Apply booster pump.

ft. full throttle

mechanical fuel

If EGTs drop, replace

causes EGTs

pump.

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

For Your Safe Flight

Page 11

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.

For Your Safe Flight

Page 12

2nd Button

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

In the LF mode holding the LF button after peak EGT is found will display the peak EGT.

In Automatic or Manual modes holding the LF button for three seconds will toggle between Standard and Normalize (NRM) views.

In the programming mode, tapping the PLUS or MINUS button will allow you to edit a parameter value.

Holding LF during power up will display the primary alarm limits after the self-test is complete.

1st and 2nd Buttons

Holding both the STEP and LF buttons simultaneously for five seconds will enter the pilot programming mode.

Just after entering Lean Find Mode (but before any EGT has risen), holding both First and Second buttons for five seconds will toggle between LOP or ROP leaning modes.

Tapping both the STEP and LF buttons simultaneously in Manual mode toggles to ‘include’ or ‘exclude’ the displayed non-primary measurement from the Automatic mode. Note: Measurements are never excluded from the Manual mode.

3rd Button

Tapping DIM (brightness decreases) or holding DIM (brightness increases) allows decrease or increase brightness respectively.

2nd and 3rd Buttons

Holding both the LF and DIM buttons simultaneously will display the Hobbs readings. Tap button labeled NEXT to see additional information screens.

4th Button ( ALL/EGT/FF )

Select what is shown during Scanner auto-sequence. Choices are ALL, EGT or FF. Highlighted one is what is active.

For Your Safe Flight

Page 13

RPM and MAP Displays

The upper left side of the display shows RPM above the MAP. The arcs represent the analog values. Percent horsepower is shown to the lower left of MAP.

63% HP

Scanner Displays

Scanner EGT and CHT Analog Bar Graph

The height of each column represents a EGT or CHT or TIT (if installed) temperature. The graph resolution depends on the programmed span between the top and bottom of the range marks. Note: when in certain modes, such as leaning or normalize, the EGT resolution will temporarily be finer.

Cylinder Numbers and Index

Just below the bar graph columns are numbers identifying the respective cylinder. If TIT is installed, it is labeled by the letter T underneath. A square ‘Cylinder I.D. Index’ surrounding a number indicates what cylinder is currently selected and relates to the digital display.

Scanner Digital Display

Located under the Scanner bar graph area is the alphanumeric display. It displays alphanumeric values for different parameters as well as status and alarm messages.

For Your Safe Flight

Page 14

Normalize / Standard View

To toggle between Standard and the Normalize views, hold the LF button for three seconds until the NRM icon toggles on or off. Note: Normalize cannot be activated while in Lean Find mode.

Standard view (when the NRM icon is not lighted): the EGT represent absolute temperature. The top of the columns indicate absolute temperature relative to the adjacent range mark temperature scale. A maximum height column depicts the temperature at the top of the range mark scale (or more), while no column represents the temperature at bottom of the range mark scale(or less). The Standard view permits comparison of EGTs across all cylinders.

Normalize view (when the NRM icon is lighted): the EGT represent the difference in temperature from the mid-point of the range mark scale. When you change to the Normalize view, all EGT columns are initially normalized to the mid-point for deviation trend analysis. Any changes are shown as an increase or decrease relative to the mid-point, thus giving an instantaneous indication that an EGT has deviated. You normally use normalize in level cruise, but it is also useful during steady state run-ups. Note: A common misapplication is to be in the Normalize view and then change power setting. This causes all columns to go off scale, high or low. Select Standard view before changing power or altitude.

Temperature Units (°F or °C)

The EDM can display engine temps in either °F or °C (Fahrenheit or Celsius). In Primary configurations, this is set to the same units as the configuration the aircraft was originally certified to.

For Your Safe Flight

Page 15

Linear Bar Graph Displays

The linear bar graphs are arranged in a three by three matrix on the right half of the display. A typical layout is depicted here (Note: your actual configuration may vary). Typical functions that can be displayed are:

Oil temperature

Oil pressure

Fuel pressure

Bus voltage

Amps (charge/discharge shown)

OAT

Fuel flow

Left tank fuel quantity *

Right tank fuel quantity *

*The fuel quantity gauges will not be functional until the fuel calibration process has been completed.

The range of the bar graphs depends on the programming. Range, redlines and/or limits are typically set to match the original aircrafts gauge markings. These are locked for Primary installations, however non-primary gauges can be user modified, using ‘EDM Config’ which is currently available through the front panel buttons. Editing of Gauge Layout requires EDM Software version 1.20.489 or later. Note: Amps can operate either as a charge/discharge or load meter, depending on programming. For charge/discharge, the center of the bar is zero and the top and bottom are maximum charge and discharge, respectively.

For Your Safe Flight

Page 16

Remote Auxiliary Display

See the important note on page 1 regarding the RAD.

The remote auxiliary display ‘RAD’ provides redundancy and allows positioning a smaller display directly in front of the pilot. Upon power up the RAD displays the EDM’s

programmed configuration (aircraft make and model and primary status). Confirm that it matches your aircraft configuration before using the instrument. This auxiliary display will normally show RPM and MAP, but will display a blinking alarm message, duplicating the alarm indication of the EDM. For example, low calculated fuel remaining of 7.7 gallons would show:

Hobbs Display

Holding both the LF and DIM buttons simultaneously will display the Hobbs times similar to the example below:

HOBBS Times

EDM HOBBS: 127.4

Engine HOBBS: 120.6

Flight HOBBS: 2.7

Flight Duration: 02:42:21

Dimming the Display

Automatic dimming is provided to dim both the panel display and the remote alarm display. You can manually adjust brightness by tapping (decrease brightness) or holding (increase brightness) the DIM button.

For Your Safe Flight

Page 17