Garmin RS-232 User Manual

™

Microflo-L

Digital Fuel

Management System

with interface to LORAN-C and GPS receivers with

RS-232 output format

OPERATING MANUAL

Single and Twin Engine Indicators

For P/N: 91204XT-38-D

Shadin

TABLE OF CONTENTS

1. GENERAL DESCRIPTION..........................................................................3

1.1 THE SYSTEM PROVIDES.........................................................................4

1.1.1 SPECIFIC RANGE............................................................................4

1.1.2 FUEL TO DESTINATION................................................................4

1.1.3 FUEL RESERVE...............................................................................4

1.1.4 ENDURANCE...................................................................................4

1.1.5 FUEL FLOW.....................................................................................5

1.1.6 FUEL USED......................................................................................5

1.1.7 FUEL REMAINING..........................................................................5

1.2 SYSTEM COMPONENTS...........................................................................6

1.2.1 FUEL FLOW TRANSDUCER..........................................................6

1.2.2 LORAN-C OR GPS RECEIVER.......................................................6

1.2.3 PANEL MOUNTED UNIT...............................................................6

1.3 TEST FUNCTION........................................................................................7

2. PREFLIGHT PROCEDURES.......................................................................8

2.1 INITIAL PROGRAMMING.......................................................................8

2.2 PREFLIGHT CHECK .................................................................................9

2.3 NO FUEL ADDED......................................................................................10

2.4 FUEL TANKS FULL .................................................................................10

2.5 PARTIAL FUEL ADDED..........................................................................11

2.6 CORRECTING FUEL ON BOARD ENTRY ERROR...........................11

3. INFLIGHT OPERATIONS.........................................................................12

3.1 INSTRUMENT OPERATION..................................................................12

3.1.1 FUEL FLOW...................................................................................12

3.1.2 FUEL USED....................................................................................12

3.1.3 FUEL REMAINING........................................................................12

3.1.4 ENDURANCE.................................................................................12

3.1.5 NAUTICAL MILES PER GALLON...............................................13

3.1.6 FUEL TO DESTINATION..............................................................13

3.1.7 FUEL AT DESTINATION..............................................................13

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NOT ENOUGH FUEL.....................................................................14

3.2.1

3.2.2 RESERVE FUEL WILL BE USED.................................................14

3.2.3 LOW ENDURANCE.......................................................................14

3.2.4 LOW FUEL REMAINING..............................................................14

3.3 BRIGHTNESS CONTROL.......................................................................15

4. EMERGENCY PROCEDURES..................................................................15

5. ERROR MESSAGES...................................................................................16

6. CONFIGURATION DATA ENTRY...........................................................17

7. SPECIFICATIONS.......................................................................................24

8. WARRANTY INFORMATION..................................................................26

6831 Oxford Street

St. Louis Park, MN 55426

U.S.A.

Sales: (800)-328-0584

Technical Support: (800)-388-2849

WWW.SHADIN.COM

NOTE: Though references are made in this manual to fuel measured
in gallons, the information applies equally to measurements in
pounds, kilos, or liters.

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Microflo-L

Although not required by the FAA, it is recommended that this
manual be attached to the FAA-approved Flight Manual, or always
kept on board for reference.

™

1. GENERAL DESCRIPTION

Microflo-L™ is a Digital Fuel Management System designed to
provide complete fuel management information under real flight
conditions without any manual entry of data (after entry of the
initial fuel on board information).

Microflo-L™ is connected to the engine fuel flow transducer for
fuel flow information and to the Loran-C or GPS receiver serial port
for navigation data (ground speed, distance and estimated time en
route).

This system is also capable of transmitting the fuel information to
the Bendix/King KLN-88, KLN-90, and Garmin GPS navigation
receivers, except the Garmin 100, for additional calculations and
display of fuel management data.

Microflo-L™ is set up to measure the flow of fuel in either gallons,
liters, pounds, or kilos, and it can be installed on virtually any
reciprocating or turbine engine by selecting the proper size fuel
flow transducer.

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1.1 THE SYSTEM PROVIDES

1.1.1 SPECIFIC RANGE
Specific Range (NM/GAL) = Ground Speed (Kt.)/Fuel Flow
per hour. This is an indication of how efficient the cruise is
and the optimum cruise speed can be determined by
selecting the power setting, which yields the highest nautical
miles per gallon.

1.1.2 FUEL TO DESTINATION
Microflo-L™ calculates (under real wind conditions) the
fuel necessary to reach the destination as selected on the
Loran-C or GPS receiver by multiplying the fuel flow by the
estimated time en route to the destination. (If an
intermediate waypoint is selected for navigation purposes,
the displayed fuel to destination represents the fuel needed
to reach the intermediate waypoint unless the distance to the
destination is in the serial message.)

1.1.3 FUEL RESERVE
Microflo-L™ calculates the amount of fuel which will be
available on board when the aircraft reaches the destination
or waypoint indicated on the Loran-C or GPS receiver. This
feature provides the pilot with accurate information so that
the reserve fuel situation can be evaluated and action can be
taken if necessary. (If an intermediate waypoint is selected
for navigation purposes, the displayed fuel reserve
represents the fuel reserve at the intermediate waypoint
unless the distance to the destination is in the serial
message.) Fuel Reserve = Fuel Remaining – Fuel to Reach
Destination.

1.1.4 ENDURANCE
Microflo-L™ calculates the time left to fly in hours and
minutes based on the fuel remaining and the present fuel
flow.

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1.1.5 FUEL FLOW
The system provides a digital readout of the fuel per hour to
a tenth of a gallon up to 100 gallons and to the nearest
gallon above 100 gallons. For the pounds version, the
readout is to the nearest pound up to 999 lbs./hour and to the
nearest 10 lbs. above 999 lbs./hour.

1.1.6 FUEL USED
The system keeps track of the fuel used since the last fuel
entry or reset.

1.1.7 FUEL REMAINING
The system keeps track of the fuel remaining on board. Fuel
Remaining is equal to Initial Starting Fuel minus Fuel Used.

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1.2 SYSTEM COMPONENTS

The system consists of three (3) basic units: the fuel flow
transducer, the navigation receiver (Loran-C or GPS) and the panel
mounted unit.

1.2.1 FUEL FLOW TRANSDUCER
The fuel flow transducer mounted in the fuel line measures
the flow of fuel and generates electrical pulses directly
proportional to the fuel flow. The transducer is fail-safe
designed, and stopped rotor will not interrupt fuel flow to
the engine.

1.2.2 LORAN-C OR GPS RECEIVER
The Loran-C or GPS receiver provides ground speed,
distance, and estimated time en route through the serial port.

1.2.3 PANEL MOUNTED UNIT
All system electronics, function controls and digital displays
are contained in a single instrument that mounts in a
standard 2¼” hole. This unit requires no periodic
maintenance, adjustment, or calibration once it is properly
installed.

The Display: The fuel flow is always displayed on the left side of
the display window. All other functions, with the priority for the
rotary switch functions, are displayed on the right side of the
display window.

System Memory: The system includes a non-volatile memory that
retains fuel remaining and fuel used information when the power to
the unit is shut down.

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1.3 TEST FUNCTION

Diagnostic software is built into the system. To activate it, press
the ENTER/TEST button until all of the display digits fill with a
checkerboard pattern, and then release it. This display will flash on
and off three (3) times. Next, all digits will be filled with a second
checkerboard pattern, the inverse of the first, which will also flash
on and off three (3) times. Careful monitoring of these patterns will
verify operation of every element of the display unit.

If the test is successful, the word “GOOD” will appear in the
display window for three seconds. (If the test is not successful, the
word “BAD” and an error message identifying the error will be
displayed. In such case, the unit will cease to function and must be
considered unserviceable until corrective action is taken.) This is
followed by:

1) The K-factor setting (Pulses Per Gallon) and units of measure

the system is set to (gallons, liters, pounds or kilograms).

2) LT ( ): Loran or GPS Type (without signal, will display ‘LOF’)

3) The distance to waypoint or destination as shown on the Loran-

C or GPS receiver to check the data interface integrity. (not
available without signal)

4) Maximum usable fuel setting.

5) Software version.

6) If the system is not capable of reading the navigation receiver

data, the word “LBD” will appear in the display window.

NOTE: a) Using the test function while the engine is running will

cause the computer to lose 17 seconds of fuel count.

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2. PREFLIGHT PROCEDURES

MICROFLO-L is a fuel flow measuring system and NOT a
quantity-sensing device. A visual inspection and positive
determination of the usable fuel in the fuel tanks is a necessity.
Therefore, it is imperative that the determined available usable fuel
be manually entered into the system.

2.1. INITIAL PROGRAMMING

The function of initial programming is to enter the total usable fuel
into the memory. It can then be recalled whenever the fuel tanks
are filled up to the maximum usable fuel. The “Full” fuel setting
determines the maximum amount of fuel that can be entered by any
method into the Microflo-L.

PROCEDURE:

1. Power the unit up.

2. Move the ADD/FULL toggle switch to the FULL position and

hold for the entire procedure.

3. Simultaneously press the ENTER/TEST button and move the

USED/REM toggle switch to the REM position. The system
will then count down for 15 seconds, displaying the count on
the left in the display window.

4. The word “FUL” and the current full fuel value will appear in

the display window. Release the ENTER/TEST button and
USED/REM toggle switch. Keep holding the ADD/FULL
toggle switch in the FULL position.

5. Move the USED/REM toggle switch to the REM position to

increment the full fuel number or to the USED position to
decrement the number. (The longer you hold the switch in
position, the faster the number will be updated.)

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