What are the Features and Specification of EDM 830 System?

EDM 830If you are looking to upgrade your cockpit with a new EDM look no further than the EDM 830 manufactured by World leader in EDM’s – J.P. Instruments.

For the next couple of years at least, the EDM 830 is going to rule the pack because the EDM 830 through its brilliant full-colour graphical LCD display totally revolutionizes the way aircraft engines are monitored.

Despite its small size (probably the smallest aircraft EDM in the market), it easily packs more features, functionality, and information in its onto its LCD screen than any other currently available aircraft EDM on the market. The latest feature addition is the Oil pressure gauge.

Being small in size is not the only reason that the EDM 830 can be easily mounted – the 830 incorporates a standard 3-4/8″ format that can be mounted vertically (portrait) or horizontally (landscape) orientation. Behind the panel, the EDM 830 only requires 2-1/2″. Connect the power supply, correctly plug-in the various cables from the aircraft sensors and you’re done – the EDM 830 is ready to fly when you are. And of course, the EDM 830 is FAA STC/TSO approved and comes with a 3-year warranty.

Here’s a short list of the main features and functions of the EDM 830:

1. RPM and manifold pressure with full graphical depiction. Display includes: RPM, MP, %HP, IAT, CDT, OAT, CAT, OIL

2. Pilot programmable engine parameters. P, OIL T, CHT, EGT, VOLTS, EGT, DIF, CLD, F FLOW, F USED, F REQD, F ENDUR and F REM

3. Percent Horsepower display.

4. Lean of peak or Rich of peak operation at the touch of a button. EGT 4 or 6 Probes, CHT 4 or 6 Probes

5. Full featured fuel flow computer system. Volts, Shock Cooling

6. GPS enhanced fuel management. LOP/ROP JPI Exclusive Leaning Mode

7. Full EDM scanner functionality. Fuel Flow (USED, Remaining, GPH Endurance, GPS Destination)

8. When fitting, EDM can be oriented as per pilot convenience and display will auto-configure. MAP, Oil Temperature, Oil Pressure, OAT

9. EDM 830 can be used in 4, 6, 7, 8 or 9 cylinder engines and Turbocharged engines. The % HP (Requires OAT, RPM, MAP, & FF). The EDM 830 comes with Power Connector and all required harnesses. EZ Trends software is included. Data recording – 100 hrs Downloadable via USB port.

Optional functions of the EDM 830 include: CDT, IAT, CARB Temperature and TIT Probes

Accessories available include: Single series fuel flow (with or without) transducer, fuel flow harness (10-04650). These are available for 4 and 6 cylinders aircraft engines too. Also available are the EDM TIT probe with shield and extension wire as also the EDM OIL temp. probe.

Little wonder then, the EDM 830 manufactured by J.P. Instruments is amongst the best aircraft EDM’s on the market today. More information here: https://www.jpinstruments.com/shop/edm-8301/


Key Features of RPM Standard Sensor in Aircraft

RPM Standard SensorBased on the model of the magneto installed in your aircraft, there are several different models / types of RPM standard sensors for aircraft. The RPM standard sensors you select and use would therefore depend on the brand of magneto in your aircraft.

Typical RPM standard sensors (as manufactured by J P Instruments) include:

RPM Standard Sensor for pressurized BENDIX 1200 SERIES (JPI part # 10-05459)
RPM Standard Sensor for pressurized BENDIX 20 SERIES (JPI part # 10-05460)
RPM Standard Sensor for pressurized BENDIX DUAL MAG SERIES (JPI part # 10-05461)
RPM Standard Sensor for VENT PLUG SENSOR for BENDIX (JPI part # 10-05651) and,
RPM Standard Sensor for VENT PLUG SENSOR for SLICK (JPI part # 10-05652).

From the year 2002 onwards, IO-550 magnetos usually have a compatible RPM sensor installed (running on 5v), but you can opt for the better-quality RPM standard sensor manufactured by JPI.

Since we can’t write on each and every one of the RPM standard sensors, let us concentrate on the more popular RPM standard sensor for the pressurized Bendix series (manufactured by Teledyne Continental Motors).

Being simple in construct, the Bendix Magneto RPM standard sensors is easily maintained and therefore quite cost effective. Also, the Bendix Magneto RPM standard sensors manufactured by J.P. Instruments is highly accurate.

If you have just acquired an aircraft of your own and are not sure of the importance of the Aircraft Sensors – here’s what it does:

The aircraft has sparkplugs and these require high voltage power. Rather than rely on the aircraft battery, the power to the spark plugs comes from a mini power generator called the ‘Magneto‘ – of which, there are different brands; the Bendix brand being more popular. The Bendix Magneto is a small power generator that has a built-in breaker switch, a transformer and a distribution system to channel the power to the spark plugs.

This power generator has a rotating magnet inside and it is important that it rotates at a speed that is within the prescribed range otherwise your spark plugs (and hence the engine) will misfire. To ensure all is well, you need the aircraft RPM Sensor. The RPM standard Sensor plugs directly into the magneto and transmits data to your EDM in the cockpit.

It is important to have a good quality RPM standard sensor as it helps identify / eliminate the magneto as the source of engine problem.

When fitting your new RPM standard sensor, make sure:

• The RPM Sensor is aligned with the correct vent plug of the magneto (if you peep through, you should see the rotating magnet in this hole. If you see a ‘gear’ you’re on the wrong vent).

• A 4 cylinder engine should read 3600 rpm, a 6 cylinder engine should read 2400 rpm, a 8 cylinder should read 1800 rpm while a 9 cylinder engine should have an rpm of 1600. A 4 cylinder dual mag engine should have rpm of 1800 and a 6 cylinder dual mag should have rpm of 2400.

• The red wire to the RPM standard sensors should be supplying 5v+.

More information on JPI manufactured RPM standard sensors here: https://www.jpinstruments.com/shop/rpm-sensor-for-bendix-mag/

How to Install Fuel Flow Transducer 201B in Aircraft?

Fuel Flow Transducer 201BThis question comes up often enough so we decided to write on how best to install the fuel flow transducer model 201B manufactured by J.P. Instruments in an aircraft.

Orientation of the 201B fuel flow transducer:

To start off and assuming you have removed the existing fuel flow transducer, hold up the new 201B fuel flow transducer in a horizontal position with the three wires up – because this is exactly how it is to be fitted. Fitting the fuel flow transducer any other way will lead to its failure. When the fuel flow transducer is in the horizontal position, the rotor within it are proper oriented and aligned with fuel flow. This is how it is meant to operate. Also, while fitting it, be sure that there is no bend closer than 6 inches either in the inlet or outlet pipe i.e. no bends before or after the transducer. Also, do not use aluminium or brass fittings when installing the 201B fuel flow transducer – use only AN816-7 Steel. The transducer is engineered to seal tight so do not use Teflon tape, or other thread sealant compound of any kind. Also, the transducer is marked IN and OUT for the fuel lines – so make sure you attach it correctly or the rotor will malfunction. The maximum torque should not exceed 15 ft lb (180 lbs.) or roughly, two full turns past hand tight.

Installation location:

If your aircraft has a carburettor, the fuel flow transducer should ideally be at the same height as the carburettor. If it is higher, fit an anti-siphon loop in the line that peaks higher than the transducer. If your aircraft sports a fuel injected engine, fit the fuel flow transducer between the engine fuel pump and the servo regulator. If your aircraft has that unique vapor return line, install the fuel flow transducer between the servo regulator and the flow divider (spider).

We have seen aircraft with Fuel Flow Transducer mounted between the electric boost pump and the mechanical pump – this is not recommended. Also, please do not hard mount the transducer to the engine as engine vibration can damage the internal rotor or cause it to malfunction and give misleading results. When installing the 201B fuel flow transducer, the wires are to be connected to the EDM. The fuel flow transducer gets its power supply (12V) directly from the EDM. Also, the wires should not be route along with or adjacent to ignition wires, alternator wires, spark plug leads, or cabin heater ignition wires.

When done, set the K-factor. The Fuel Flow Transducer 201B will have a K-factor of ~29.


It might be worthwhile to also procure a Fuel Flow Tester (just $35.00) for testing instrument and transducer.

Fault finding:

Some pilots called in to report consistently high fuel flow readings. If you have followed above installation procedure correctly, check for air entering system at selector valve (may require a change of the O-ring). Here’s a test: The next time the aircraft is flown in cruise, turn on the boost pump for one minute. If the fuel flow drops, then this is an indication that air is leaking into the fuel line upstream of the transducer. It is possible that air is leaking into the system through the seal valve or other connection. Fuel stain may not be visible.

Features & Specification of EDM 960 Twin System

EDM 960 Twin SystemEDM 960 manufactured by J.P. Instruments is available four, six, seven, eight and nine-cylinder aircraft engines configurations. The EDM 960 is designed to be a pilot’s personal flight engineer – one that is always working in the background and constantly watching over the aircraft engine while the pilot concentrates on flying the aircraft.

The EDM 960 actively monitors the aircraft engine four times per second and sound/ display a warning if any part of the aircraft engine does not confirm to the pre-set parameters.

Here are the specifications of the EDM 960 Twin System manufactured by J.P. Instruments:

1. Hands-free, automatic scanning
2. All programming done from the Front Panel
3. LeanFind™ finds the first and last cylinder to peak with true peak detect eliminates false peaks
4. Displays both leaned temperature below peak and peak
5. Battery voltage with alarm
6. Amperes (load or charge/discharge meter)
7. Programmable alarm limits
8. Normalize view
9. Exhaust Gas Temperatures (EGTs) to stable 1°F resolution
10. DIF low to high EGT with alarm
11. EGTs to stable 1°F resolution
12. Shock cooling monitored on every cylinder
13. User selectable index rate
14. Fast response probes
15. Non-volatile long-term memory
16. Records and stores data up to 30 hours
17. Post-flight data retrieval
18. Download to Palm™ Computer
19. Data retrieval software
20. Oil pressure
21. Oil temperature
22. Outside air temperature
23. Fuel level
24. Adjustable display
25. Adjustable order of display

These are the main features of the EDM 960 Twin System:

The EDM 960 displays engine measurements on a liquid crystal display (LCD) screen and also on a remote auxiliary display (RAD). The RAD intelligently places critical information directly in front of you. After the initial self-test, the pilot will be requested to punch in the fuel information i.e. total fuel added or fuel in the tank.

The RAD unit will also display the rpm and manifold pressure. The display screen is divided into three sections – top left is for the rpm and manifold pressure. The bottom left is the scanner section while the right side of the display is for the bar graphs.

The bar graph also displays the numerical values of each bar. If any power settings exceed pre-programmed limits, a blinking alert icon along with a blinking message is displayed in the scanner section.

The default displays of the EDM 960 Twin System include oil temperature, oil pressure, fuel pressure, bus voltage amps, outside air temperature, fuel flow (left), fuel quantity and (right side) fuel quantity.

The EDM 960 collects data and displays it for you in a useful way. The EDM 960 monitors engine temperatures, pressures, fuel quantities, fuel flow, and voltages. It is invaluable for adjusting the fuel air mixture and for diagnosing engine malfunctions. On the left of the display is the EGT Probe graphed. There’s also the CHT bar graph and below it the number corresponding to the engine cylinder number.

There are four buttons on the front panel. The button labels can be changed depending on how the display has been arranged by the pilot.

The features of the EDM 960 Twin includes auto indexing i.e. 10 minutes after the EDM 960 is turned on it will automatically index through all measurements. Tapping the step button will take you into the manual indexing mode here you can observe each measurement value for as long as you want. You can find more information here: https://www.jpinstruments.com/shop/edm-960/

Usage and Significance of CDT Probe in Aircraft

CDT ProbeThe Compressor Discharge Temperature (CDT) probe (not to be confused with Conductivity, Temperature, Depth probe used in ships and also called CDT probe), is installed in the engine compartment just after the inter-cooler. The probe is installed with a #40 stainless steel clamp. A large clamp is supplied to fit around the air-port leaving the inter-cooler.

A typical CDT probe kit from J.P Instruments includes the thermocouple type ‘K’ CDT Probe, a stainless steel clamp thimble, one stainless steel exhaust seal washer and one stainless steel screw type clamp.

Working of the CDT in an aircraft: The CDT probe senses compressor discharge temperature of the aircraft compressor and for this purpose, the probe is mounted external to the flow path that receives high pressure air discharged from the compressor. This air flows past at least one thermocouple which in turn measures the high-pressure air temperature and the high-pressure air is then returned to the flow path.

Basically, air from the compressor is discharged through a hole bored into the engine case. This air is then channelled into a housing containing the CDT probe which measure the air temperature flowing over it. The CDT probe in turn sends an electrical signal to the connected EDM Monitors or electronic control unit which in turn indicates the compressor discharge temperature to the pilot. The air is then vented to a sink pressure and can be used as cooling or purge flow.

The purpose of wanting to know the comp discharge temp is to prevent chances of detonation that can happen due to excessive heat. The intercooler cools the air so much that the limit temp is never reached, or even approached, so the original equipment CDT gauge becomes irrelevant. Fundamentally you want to know the inlet temp limits for the engine and the temp of the air at this point. If the CDT is below this temp, you are fine. If CDT is above this, it depends on the conditions and the efficiency of the intercooler (or aftercooler as is technical called ).

As we are aware, CDT can be critical under certain circumstances e.g. staging a dual annular combustor for a high bypass turbofan commercial jet engine where fuel-to-air ration can be critical.

JPI CDT probes are superior because of their response speed. Ungrounded (insulated) probes sold by rival manufacturers are too slow to respond to all temperature changes. It is also worth noting that insulated probes, starting at the same point as grounded probes, never achieved true temperatures. The ungrounded, insulated probes are generally 3/16″ in diameter whereas, JPI’s grounded probes are only 1/16″ in diameter. The fatter temperature probes manufactured by the rivals have more surface are and therefore lose energy a rate of T’/ This is another reason JPI uses thin probes and not sluggish probes.

Also, JPI’s grounded probes are manufactured using a space-age material, Hastaloy-X, that can withstand the harsh sulphur atmosphere of temperature exhaust gas and uses them in all its gages. You can select and buy CDT Probes here: https://www.jpinstruments.com/product-category/probes-sensors/

Aircraft’s Fuel Scan 450 Twin: The Best Aviation Consumer’s Product

Aircraft's Fuel Scan 450 TwinThe aircraft fuel scan 450 Twin manufactured by J.P. Instruments, is probably the best fuel indicator to date. This is a product engineered by aeronautical engineers (nothing new there), but; hold your breath, was designed by bunch of experienced pilots which is why it has all the features and functionality that you as the pilot or aircraft owner might love to have in a fuel indicator.

I won’t insult your intelligence by writing that this is a digital fuel indicator! Of course, it is digital – which modern day fuel indicator isn’t? That said and for its size, it uses an amazing display system – one that is not only crystal clear, but has the priorities right. So, let us check out the features offered by aircraft fuel scan 450 Twin manufactured by J.P. Instruments.

Product features of by aircraft fuel scan 450 Twin manufactured by J.P. Instruments

1. Fuel quantity measured in gallons, litres or pounds.
2. Low fuel quantity alarm.
3. Low fuel time alarm.
4. GPS interface—bi-directional serial interface.
5. Automatic K-factor calculation.
6. Instantaneous fuel flow rate
7. Solid-state pulse generating rotor fuel flow transducer.
8. Total amount of fuel consumed.
9. Total fuel remaining.
10. Time to empty at the current fuel-flow rate.
11. Fuel Management.

One thing that obviously hasn’t changed is the fact that the pilot has to still enter the quantity of fuel filled into the tanks. He can do so while the aircraft is on the ground or even after take-off. Naturally, the accuracy of some of the functions of the aircraft fuel scan 450 Twin depends on accuracy of the fuel quantity entered by the pilot.

That said, let us see how different the aircraft fuel scan 450 Twin vis-à-vis earlier fuel indicator models. For starters, the FS-450 Fuel Scan uses a small, highly compact turbine transducer that measures the fuel flowing into the engine. The working principle of the transducer is similar to that of a regular power generator – the faster the wheel spins, the more the power output. This ingenious simplicity ensures that the transducer keeps performing accurately even if the aircraft was doing cartwheels in the air.

In terms of accuracy, fuel transducer does to the fuel indicator what HD technology did to your TV set i.e. the high rate of pulses generated by the transducer, ensures higher accuracy in calculating fuel flow.

Having the fuel flow accurately measured; thanks to modern day IC-based circuits and programming, the rest of the requirements on the pilot list was easy to implement.

The functionality of the aircraft Fuel Scan 450 Twin manufactured by J.P. Instruments includes:

Operating Modes: There are two operating modes – Automatic Indexing, and Manual Indexing.

Programmable Alarms: Pilot programmed minimum Fuel Flow indicators that will display fuel remaining and finally, time of flight left until the tanks become empty.

Sleep Alarm: Don’t want to be distracted by the alarm? Just press the STEP button and the alarm will ‘sleep’ for 10 minutes or, press and hold a couple of seconds and the alarm will turn off.

Automatic Self–Diagnostic testing on engine start after which, it will remind you to enter fuel you might have added to the tanks.

These and several other functions and features, make the aircraft fuel scan 450 Twin manufactured by J.P. Instruments an awesome product. It is hardly surprising therefore, that it has been declared as the best aviation consumer product for this year. More information here: https://www.jpinstruments.com/shop/fuel-scan-450-copy/

JP Instruments EDM-740 – Colour Engine Monitor for Experimental Aircraft

Engine Data Management 740 Experimental SystemAircraft Engine Data Manager 740 for experimental aircraft is an awesome product that is innovative and aggressively priced.

Starting at $2899 for a 4-cylinder installation and $3250 for a 6-cylinder one, the EDM-740 covers all the basics that a pilot requires to fly the aircraft safely. This includes the most of the popular sensors. Optionally you can add turbine-inlet temp, electrical-bus current, carb temp and fuel pressure sensors. Also, if you have the sensors installed, it can also read resistance or capacitance of fuel-level senders.

Similar to earlier EDM’s, the EDM-740 stacks EGT and CHT Monitors so you can view all cylinders at on go. Also, the EDM-740 display will automatically self-adjust when used in a 4-cylinder aircraft or 6-cylinder aircraft. Unlike EDM’s manufactured by others, there are no “missing bars”. Also, you can choose the order of the subordinate menu display.

Fitting your new EDM-740 is a breeze. The EDM-740 requires just 3.125” of space. The panel is just 2-inches deep and the faceplate is 4.23(h) by 3.195 (w). You can even re-orient the display to suit your requirement.

Key features of the EDM-740 include:

1. User-defined upper and lower limits, alarms.
2. Large single-line display that magnifies the values of other indications.
3. LF button on faceplate for Lean Find.
4. In default mode, single press of LF button will display ROP and enter lean-find mode.
5. The EDM-740 is equipped with an engine-power calculator.
6. The EDM-740 has a faceplate mounted LDR (ambient light sensor) which in turn automatically adjusts the display intensity so that even cross-cockpit, the 740’s display is clear and legible right down to the smallest menu item.
7. Incredibly fast response – whatever manoeuvring you do, the display indicates exactly what is happening in the engine in a manner that is easily digestible to a pilot.
8. The EDM-740 also integral data logging for roughly 200 hours (at the rate of once every 6 seconds).

Functions include:

RPM Sensor Propeller
• MAP Manifold Pressure
• % HP Percent of Horse Power
• EGT Exhaust Gas Temp.
• CHT Cylinder Head Temp
• O-T Oil Temperature
• O-P Oil Pressure
• OAT Outside Air Temp.
• VDC Voltage
• GPH Gallons per Hour REQ Required to destination
• USD Fuel used
• H:M Endurance
• MPG Miles per Gal
• CLD Shock Cooling on all cylinders
• DIFF Gami spread
• USB Memory stick Data Recording
• EZ Trends Graphing program

Optional functions include:

• TIT Probe Turbine Inlets Temp
• F-P Fuel Pressure
CDT Probes Compressor Discharge
• AMP Current amps
• CRB Carburetor Temp
• L-Tank Fuel Quantity, level
• R-Tank Fuel Quantity, level

For more information on J.P. Instrument’s EDM 740, please visit: https://www.jpinstruments.com/shop/edm-740-experimental-only-3/