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Pilot’s Guide

Engine Data Management

EDM-700
EDM-800

Copyright 

 2001  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

(714) 557-5434

Fax (714) 557-9840

www.jpinstruments.com

Printed in the United States of America

Rev P 05/2001

Summary of Contents for EDM-700

Page 1: ... 2001 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 714 557 5434 Fax 714 557 9840 www jpinstruments com Printed in the United States of America Rev P 05 2001 ...

Page 2: ...S 11 DIAGNOSTIC TESTING ON STARTUP AND DURING FLIGHT 11 MODES 11 AUTOMATIC MODE 11 MANUAL MODE 12 LEANFIND MODE LEANING RICH OF PEAK 12 LEANFIND PROCEDURE GENERAL EXPLANATION 15 OPERATION FOR EACH PHASE OF FLIGHT 20 SHOCK COOLING 21 COMMON MISAPPLICATIONS 22 SECTION 4 DIAGNOSING ENGINE PROBLEMS 23 ALARMS 27 PRE IGNITION AND DETONATION 28 SECTION 5 DATA LOGGING 29 SECTION 6 FUEL FLOW OPTION OPERATI...

Page 3: ...ON 12 PROGRAMMING THE FUEL FLOW OPTION 44 FUEL FLOW OPTION PROGRAMMING PROCEDURE 45 SECTION 13 PROGRAMMING LONG TERM DATA MEMORY 46 SECTION 14 ALARM LIMITS 48 MAP FUEL FLOW ALARM LIMITS UNITS FUEL CAPACITY 51 SECTION 15 REAL TIME SERIAL DATA PORT 52 NAVIGATION DATA FORMATS 54 SETTING GPS C FUEL FLOW COMMUNICATIONS FORMAT 54 DIAGNOSTIC MESSAGES FUEL FLOW 55 NAVIGATION DATA PORTS FOR GPS COMM 55 SEC...

Page 4: ...How to Change Modes page 7 EDM 700 enters Automatic mode two minutes after power up ...

Page 5: ...rface Instantaneous fuel flow rate Total amount of fuel consumed Total fuel remaining Time to empty at the current fuel flow rate Long Term Data Memory Records and stores data up to 30 hours Non volatile memory Post flight data retrieval Download to Palm Computer Data retrieval software EDM 800 HP MAP and RPM Displays horsepower and RPM Automatically calculates percent horsepower Engine Data Manag...

Page 6: ...hat accurately measure the small temperature changes as small as 1 F that occur during mixture adjustment Temperature and Mixture In a piston engine only a small portion of the energy from combustion produces movement of the piston during the power stroke The majority of energy passes into the exhaust pipe as hot gasses By monitoring the temperature of these exhaust gasses you will have an indicat...

Page 7: ...y occurs at peak EGT Accurate leaning yields optimal engine temperatures By being able to precisely adjust the mixture your engine can produce either the best fuel economy or maximum power whichever you choose A single EGT gauge merely gives you an average of each cylinder s temperature some cylinders can be too rich while others too lean Variations produced by differences in fuel distribution ign...

Page 8: ...sting the fuel air mixture and helps diagnose engine malfunctions There are three components of the user interface Analog display including cylinder number and index dot Digital display for numeric readouts and messages Two front panel operating buttons Displays Analog Display The upper half of the face of the EDM is the analog display with HP The following is a description of the analog display f...

Page 9: ...wn as an increase or decrease in column height A one segment change in column height represents a 10 F change The Normalize view permits rapid visualization of EGT trends rather than a percentage of red line You should use normalize in level cruise and run up To toggle between Percentage and the Normalize views hold the LF button for five seconds until the display changes The analog display become...

Page 10: ... OIL The highest TIT segment will flash on when the digital display shows TIT A round dot under the numbers 1 through 6 indicates that particular column is shown numerically in the EGT and CHT digital display Bar Graph EGT and CHT Each column in the bar graph is composed of a stack of segments The total height of each column represents the EGT and the missing segment in the column represents the C...

Page 11: ...t to ambient lighting conditions Modes There are three standard operating modes of the EDM Automatic Manual and LeanFind These modes will be described in more detail beginning on page 11 Most of the time you will operate the EDM in the Automatic mode When you first turn on the power the EDM starts in the Manual mode but will enter the Automatic mode after two minutes The three modes affect primari...

Page 12: ...ote pressing a button momentarily The term hold will be used to denote pressing and holding a button for five seconds or longer STEP Button Located on the lower left side near the instrument face In the Automatic mode tapping the STEP button will stop and change to the Manual mode Then each tap of the STEP button will display the next parameter in the sequence In the LeanFind mode tapping the STEP...

Page 13: ...EGT In the LF mode tapping the LF button will mark a data record in long term memory and display will flash SNAP Secondary functions of the LF button include In the pilot programming procedure holding or tapping the LF button is used to increment or decrement parameter values and toggle between Yes and No answers to questions STEP and LF Buttons Holding both the STEP and LF buttons simultaneously ...

Page 14: ...emperature 22 CRB Not available when CDT is installed Difference between hottest and coolest EGT 80 DIF Dot indicates most widely deviating cylinder EGT CHT I340 376 EGT left CHT right Dot indicates cylinder TIT Turbine Inlet Temperature I370 TIT I370 TI2 Turbine 1 left Turbine 2 right Oil Temperature I 7 8 OIL Shock Cooling 30 CLD Dot indicates fastest cooling cylinder The display will pause at e...

Page 15: ...for inconsistent or intermittent signals A faulty channel or probe encountered during start up or during flight will be deleted from the sequence producing a missing column or blank digital data Modes The EDM has three different operating modes Automatic Manual and LeanFind When you first turn on the power the EDM starts in the Manual mode but will enter the Automatic mode after a few minutes The ...

Page 16: ...hen you want to monitor one specific parameter such as shock cooling during descent or a particular cylinder temperature during climbs To change to the Manual mode tap the STEP button once Subsequent taps will index the digital display through the parameter sequence see Parameter Scan Systems without Fuel Flow Option on page 10 To exit the Manual mode and return to the Automatic mode either tap th...

Page 17: ...the procedure for the lean of peak method The default method is set to rich of peak Simply pre lean tap the LF button and begin leaning Upon reaching cruise configuration you will use the LeanFind mode to identify the first cylinder to reach peak EGT ...

Page 18: ...LeanFind mode is active 6 Stop leaning when a column begins flashing You will see LEANEST for two seconds followed by I545 SET or with Fuel Flow I545 I 2 4 Flashing cylinder dot column indicates leanest cylinder SET means Set the mixture Due to thermal inertia this will usually be about 15 F lean of peak 7 If you hold LF peak EGT will be displayed while the LF button is held down I560 PK Captured ...

Page 19: ... know your aircraft s limitations Pre lean the mixture to about 50 below peak After pre leaning wait for one minute for the temperatures to stabilize Next begin the leaning process by tapping the LF button This tells the EDM to begin looking for a 15 rise in EGT for any cylinder Begin leaning the mixture When a 15 rise occurs eliminating false peaks the LeanFind mode becomes activated shown when t...

Page 20: ...ds followed by flashing the column and displaying the value of the EGT of the cylinder that peaked first The word SET will also be displayed With the Fuel Flow Option the current fuel flow rate will be displayed on the right side of the digital display instead of the word SET The flashing cylinder will be locked or set into the digital display during the remainder of the LeanFind procedure to allo...

Page 21: ...n too much the EGT will drop and the engine will be operating lean of peak Lean of Peak Leaning with GAMI injectors To use the lean of peak method tap LF and then immediately hold both STEP and LF until you see LEAN L Once you begin leaning ...

Page 22: ...ng process for turbocharged engines is by reference to the first cylinder or TIT to reach peak However the TIT factory red line may limit the leaning process TIT red line is generally 1650 F and up to 1750 F in some installations In the LeanFind mode the T column TIT is included in the procedure If during leaning the TIT exceeds red line by less than 100 for less than one minute the LeanFind proce...

Page 23: ...For Your Safe Flight Page 19 the factory installed probe and gauge and this gauge reading is the limiting factor when adjusting your engine ...

Page 24: ...to operation indicates fouled spark plug Include your EDM on your run up checklist Take Off Climb and Full Throttle Operations Suggested setup Percentage view Automatic mode Verify EGTs and CHTs consistent with past climbs EGTs should be the 1100 to 1250 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 inj...

Page 25: ...etup Percentage view Manual mode Be alert for CLD shock cooling alarm is set to 60 F Average cool rates of 40 F minute to 60 F minute are normal depending on the engine size Shock Cooling Cooling the cylinders too fast can result in cracking and eventual failure Lycoming Service Instruction 1094D March 25 1994 on Fuel Mixture Leaning Procedures states At all times caution must be taken not to shoc...

Page 26: ...the speed of approximately 10 F per second Off scale EGT bars too high or low You forgot that you set the EDM in the Normalize view and later observe off scale EGT bar readings The higher sensitivity of the Normalize view can quickly go too high or low off scale with only small changes in EGT First cylinder to peak is not the hottest This is normal The first to cylinder peak is not necessarily the...

Page 27: ...0 F oil cooler thermostat opens at 180 F Shock cooling 40 minute 55 minute 200 minute tightly cowled Bonanza helicopter Maintain a cooling rate of less than 60 minute You will find that the cylinder with the greatest shock cooling will shift from front cylinders during climb out to the rear cylinders during descent If one CHT is reading 20 to 50 above or below the others this may be due to that cy...

Page 28: ...Page 24 Engine Data Management available to occupy the same socket as the factory original probe Contact your dealer ...

Page 29: ...ve plugs checked EGT Increase or decrease after ignition system maintenance Improper timing high EGT retarded ignition low EGT advanced ignition Check EGT for each magneto to determine any uneven timing Loss of EGT for one cylinder Engine rough Stuck valve Other cylinders are okay Have valve train checked Loss of EGT for one cylinder no digital EGT Failed probe or failed wire harness Swap probes t...

Page 30: ... pressure Check that the alarm limits are set to Celsius degrees Slow rise in EGT Low CHT Burned exhaust valve CHT is low due to low power output Have compression checked High CHT on cylinders on one side of engine Obstruction under cowling Check for improper installed baffling cowl flap misalignment or bird nests EGT on one cylinder jumps up and down 100 Spark plug fouling at higher temperatures ...

Page 31: ...s programmable alarms When a parameter falls outside of its normal limits the digital display will flash with the value and abbreviation of the alarming item If the condition triggering the alarm returns to within normal limits the display will stop flashing the alarm If your installation includes a separate panel mounted alarm warning enunciator light or audible warning it too will be activated T...

Page 32: ...L Low fuel quantity remaining Lowest priority LO TIME Low fuel endurance remaining Pre Ignition and Detonation Combustion that is too rapid leads to detonation and possibly pre ignition Detonation is abnormally rapid combustion where the fuel air mixture explodes instead of burning uniformly It causes the EGT to decrease and the CHT to increase and can appear during the leaning process It occurs u...

Page 33: ...less than 150 F for a carbureted engine If you discover a DIF spread greater than this identify the effected cylinder and initiate preventive maintenance Trend data for EGT and CHT is also of value Any departure from a cylinder s baseline requires investigation Refer to the Engine Diagnosis Chart on page 23 Data logging as a means of identifying trends is of considerable value in preventative engi...

Page 34: ... display in either the Automatic or Manual modes or during the pilot programming procedure The select switch does not effect the analog display Start Up Fuel After initial self test you will be asked to inform the EDM of start up fuel The EDM will display FUEL for one second and then flash FILL N until any button is pressed If your aircraft has tank fill tabs and no auxiliary tanks you can use the...

Page 35: ...FT OR REMOVED FUEL FROM THE AIRCRAFT Then tap the STEP button to complete the entry and advance to the Manual mode Adding Fuel and Auxiliary Tanks If you either a added less than full fuel to only the main tanks or b topped the main tanks but have some fuel remaining in the auxiliary tanks then select FILL and the next display will ask you how much you added 0 GAL or selected units Hold the LF but...

Page 36: ...s of measuring fuel flow you must rely on the aircraft fuel gauges or total time of flight Aircraft fuel gauges are notoriously inaccurate they are only required by the FAA to read accurately when displaying empty And measuring time of flight is only an approximation and assumes a constant fuel flow rate for each phase of flight The EDM Fuel Flow Option uses a small turbine transducer that measure...

Page 37: ...is installed T A Difference between hottest and coldest EGT 80 DIF Dot indicates most widely deviating cylinder T A F RPM 2450 RPM RPM T A F MAP 23 I MAP Manifold pressure F A Fuel Remaining 37 2 REM In gallons liters or pounds or kilograms F A Fuel required to next GPS WPT or Destination 25 9 REQ Present with GPS interface Valid signal and way point F A Fuel Reserve at next GPS WPT or Destination...

Page 38: ... A EGT CHT I340 376 EGT left CHT right Dot indicates cylinder T A TIT Turbine Inlet Temperature I370 I3 5 Turbine 1 left and fuel flow right T A Oil Temperature I 7 8 OIL T A Shock Cooling 30 CLD Dot indicates fastest cooling cylinder ...

Page 39: ...stored in the EDM or only the new data recorded since your last retrieval In either case no data in the EDM is erased The data will be saved in the Palm Computer or PC in a file in a compressed format The PC program supplied with the Long Term Data Memory will decompress the data for display and use by other programs such a MS Excel or Lotus 123 The amount of total data that the EDM can store will...

Page 40: ...e J P Instruments has a downloadable data transfer application program for the Palm series called EzPalm Downloading the EzPalm Program from the Internet Go to our web page www jpinstruments com go the Home page and then go to the downloads page Double click on EZPALM2 ZIP When the File Download window appears select Save this file to disk Save the file to folder C Palm Add on Using Windows Explor...

Page 41: ...n your aircraft instrument panel and the cradle or travel cable to the Palm Computer 2 Simultaneously hold the STEP and LF buttons for five seconds You will see the word PROGRAM for two seconds Tap the STEP button until you see the question DUMP N 3 Tap the LF button once or twice to select either NEW or ALL NEW will transfer only data newly recorded since you last saved your data ALL will transfe...

Page 42: ...mpatible format 1 Place the Palm Computer in the cradle and begin a HotSync Your file will be placed in the folder C Palm YourName Backup where YourName is the folder corresponding to your Palm Computer user name The file will have a name similar to P010318a PDB corresponding in this example to the date 2001 March 18 2 Using MS Explorer move the file P010318a PDB to the folder containing the EzSAV...

Page 43: ...T FF USD MARK is the header text and is listed in the file only once It describes the contents of each subsequent line of data starting with time in hours minutes seconds The next labels are E1 E6 for EGTs then C1 C6 for CHTs The DIF CLD OAT BAT FF and USD are the same as on the EDM 700 display The MARK field will be an S if the data was marked by pressing the LF button twice Import the data to yo...

Page 44: ...be skipped T A OAT 0 OAT I0 OAT I0 This step will be normally be skipped Adjust the indicated temperature up or down by up to 10 For example OAT 3 adjust the OAT 3 higher T A EGT I N EGT I N EGT I Y Y Yes sets the digital display to one degree resolution N No sets 10 10 resolution is easier to interpret the EGTs HP Y N Y Y Yes displays HP in the upper digital window N No displays RPM in the upper ...

Page 45: ...r Constant You must adjust the HP Constant once for your aircraft The Fuel Flow Option is required to be installed to display percent of horsepower The default display will be RPM if Fuel Flow is not operational You must perform this adjustment in the air while the aircraft is in flight 1 Enter the pilot program mode by simultaneously holding the STEP and LF buttons for five seconds 2 Tap STEP rep...

Page 46: ...sy calibration set the EDM 800 MAP to the same value as shown on your aircraft s manifold pressure gauge Tap or hold the LF button to change the MAP value OR B Absolute calibration the table below shows the MAP for a given field elevation down the left side of the table and altimeter setting along top row of the table Find the entry in the table most closely matching your field elevation and curre...

Page 47: ...nstalled probe or gauge In normal cruise flight record the difference between the factory installed TIT gauge and the EDM TIT reading TIT gauge ________ EDM ________ If you haven t already done so start the pilot programming procedure by simultaneously holding the STEP and LF buttons for five seconds You will see the word PROGRAM for two seconds Tap STEP to advance to the next item Tap the LF butt...

Page 48: ...___ To enter the number move the decimal point three places to the left For example if the K factor on the fuel flow transducer is 29 123 enter 29 12 in the K factor parameter The K factor can be changed in the pilot programming procedure When the K factor is changed during a trip calculations of fuel used fuel remaining and time to empty are not retroactively recalculated Fine Tuning the K Factor...

Page 49: ...ere Date ŒEDM fuel used actual fuel used ŽCurrent K factor New K factor ŒxŽ Pilot s initials Fuel Flow Option Programming Procedure Setting the K factor This procedure is different than for setting other parameters Place the select switch in the FF position If you haven t already done so start the pilot programming procedure simultaneously hold the STEP and LF buttons for five seconds You will see...

Page 50: ...the EDM See Setting GPS C Fuel Flow Communications Format on page 50 Section 13 Programming Long Term Data Memory If you haven t already done so start the pilot programming procedure simultaneously hold the STEP and LF buttons for five seconds You will see the word PROGRAM for two seconds To change the date time and user id for the Long Term Data Memory tap the STEP button until the display shows ...

Page 51: ...For Your Safe Flight Page 47 6 selects the first character STEP moves to the next character To Save hold both STEP and LF for 5 sec END Y Tap STEP button to exit the procedure ...

Page 52: ...een Fahrenheit and Celsius newer instruments will automatically change the alarms to the factory limits When an alarm is displayed tapping the STEP button will temporarily delete that parameter from the sequence for the next ten minutes When an alarm is displayed holding the STEP button until the word OFF appears will delete that parameter from the sequence for the remainder of the flight Changing...

Page 53: ... Tap the STEP button to advance to the next item in the list Tap the LF button to select alternate values of that item Hold the LF button to increase a numerical value tap the LF button to decrease a numerical value The shaded areas in the chart below pertain only to the Fuel Flow Option ...

Page 54: ...LD 5 CLD 200 CLD Cooling limit set in 5 min increments I650 TIT 650 TIT 2000 TIT Also sets the maximum scale of the EGT and TIT bar graph 230 H OIL 40 H OIL 500 H OIL Oil temperature high limit set in 5 increments 90 L OIL I0 L OIL 250 L OIL Oil temperature low limit set in 5 increments MAP 42 MAP 25 MAP 60 MAP overboost alarm EDM 800 only FUEL GAL FUEL GAL FUEL KGS FUEL LTR FUEL LBS Selects the u...

Page 55: ...ample if you change from Gal to Lbs the tank capacity will be interpreted as 50 Lbs rather than 50 gallons the EDM will not convert 50 Gal to equivalent pounds Main Tank Capacity Enter the total capacity of the main tanks in the fuel flow units selected If you have tank tabs but no auxiliary tanks and sometimes fill only to the tabs set the main tank capacity to the capacity up to the tabs Auxilia...

Page 56: ...our engine Exceptions 4 cylinder engine with dual all in one magnetos set to CYL 8 4 cylinder Laser ignition set to CYL 8 6 cylinder Laser ignition set to CYL I2 Section 15 Real Time Serial Data Port Serial Data Output Port Configuration The real time serial port is active only if the alarm limit parameter RECRD is set to RECRD N The RS 232 port on your computer should be configured as follows 960...

Page 57: ...ne is output as a single string with no imbedded carriage returns or line feeds and is terminated with a single carriage return CR and line feed LF If a parameter is not in the sequence it will be omitted from both the descriptor line and the data line Outside air temperature header is either OATF or OATC depending on the temperature units displayed Data line example 1390 1340 1390 1360 1420 1340 ...

Page 58: ...formats Format Baud rate NMEA 183 Marine Navigation Data Format 4 800 This is the format for most handheld GPS receivers Loran must have sentences RMA RMB GPS must have sentences RMB RMC Aviation Data Format 9 600 Output sentence type 1 Required sentences are A B C D E I and L first character identifier byte Sentence terminator may be either CR LF or CR alone Northstar Northstar binary 1 200 M1 se...

Page 59: ...ol setup is in process Verify correct output format setup in GPS receiver check GPS connections NO SIG message and parameters REQ RES MPG are missing GPS receiver has insufficient signal for valid data NO WPT message and parameters REQ RES are missing No waypoints are programmed into the aircraft GPS receiver REQ or RES message Your ground track is more than 70 from your course to the next GPS way...

Page 60: ...tion manual for 7 8 9 cylinder instruments MAP RPM 9 PIN CONNECTOR EDM 800 Fuel Flow Option 15 pin connector Pin no Pin no Probe or function Pin no Function sensor pin Pin no Function yel 1 red 2 OIL grn 1 RPM sig 1 1 RS 232 out yel 3 red 4 IND blk 2 RPM grd 2 2 RS 232 in yel 5 red 6 CARB or CDT red 3 RPM pwr 3 wht 4 FF signal yel 14 red 15 OAT red 4 MAP pwr 3 red 5 FF power yel 16 red 17 TIT blk ...

Page 61: ... 1989 Lycoming Flyer Issue 53 dated January 93 Technical Reviews and Original References For those pilots who have engineering backgrounds the references listed below present the original research on the combustion process and represent the source documents for those with technical interests A Hundere Autogas for Avgas AOPA Pilot October 1969 A Hundere and J Bert Pre ignition and Its Deleterious E...

Page 62: ... to JPI with all information requested This warranty is void on any product which has been subject to misuse accident damage caused by negligence damage in transit handling or modification which in the opinion of JPI has altered or repaired the product in any way that effects the reliability or detracts from the performance of the product or any product whereon the serial number has been altered d...

Page 63: ...ont panel 8 C CAL ERR 11 Calibration horsepower 40 internal self test 11 K factor 43 manifold pressure MAP 41 OAT 39 TIT factory original 42 Capacity fuel tank 29 CARB 49 Carburetor 51 ice 25 temperature 10 32 Celsius display indicator 6 engine temperatures 49 OAT 39 Changing alarm limits 47 CHT missing segment 6 probe 2 23 too high or too low 23 26 CLD See Shock cooling Climb 20 Combustion 2 27 5...

Page 64: ...e diagnosis chart 24 limits normal 23 run up 20 Enunciator alarm 26 Exclude parameters 12 Exhaust leak 20 26 EzCapture 36 EzPalm 35 EzRec 52 EzSAVEP 36 F Factory default alarm limits 47 Factory original TIT probe 42 Fahrenheit display indicator 6 engine temperatures 49 OAT 39 Failure to pre lean 22 FF select switch 29 Fill options 30 FILL N 29 FILL 30 First cylinder to peak 15 Flashing segment 6 F...

Page 65: ... temperature IAT 10 32 Informing the EDM 700 startup fuel 29 Injectors See Fuel injectors Intake valve 24 Interface computer 51 K K factor changing 40 44 determing 43 KPH 32 L Laptop interface 51 LBAT 49 Leak manifold 26 Leak manifold 20 Lean of Peak 17 Lean of Peak Leaning 17 Leanest cylinder 14 LeanFind button 9 description 8 mode 12 procedure 14 Leaning 2 See also LeanFind by TIT 18 pre leaning...

Page 66: ...r 4 Option connector 55 Outside air temperature SeeOAT P Palm Computer 35 Parameter indexing 10 31 Peak EGT 15 PEAK EGT 14 16 Percentage view 5 Pilot programming 38 alarm limits 47 data recording 45 fuel flow option 43 Pin assignments option connector 55 Power best 3 PPH 32 Pre ignition 25 27 Pre leaning See Leaning pre leaning Priority alarm 27 Product support 56 Programming 38 alarm limits 47 da...

Page 67: ...ark plug fouling 5 20 24 25 Startup diagnostics 11 fuel 29 STEP button 8 Stuck valve 24 Switch select 29 T Tabs tank 50 Take off 20 Tanks fuel capacity 29 50 tabs 29 50 Tapping a button 8 Technical support 56 Test self 11 Time to empty 32 Timing ignition 24 TIT 10 18 factory original probe 42 missing segment 6 Toggle N P 5 Top fuel tanks SeeFill Total fuel 31 used 32 Transducer fuel flow 31 Transf...

Page 68: ...Page 64 Engine Data Management EDM 700 Data Logging Worksheet A C N ________ Make ______ Model _____ Engine _________ EGT CHT RPM Date Tach Alt 1 2 3 4 5 6 TIT DIF MP ...

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