Dual Fuel Level (FL-2RA-12, FL-2RA-24 and FL-2CA) (2nd Generation Instruments) Operating and Installation Instructions OI 0131941A 10/15/01 You must read this manual before installing or operating the instrument. This manual contains warranty and other information that may affect your decision to install this product and/or the safety of your aircraft. Model: S/N: Electronics International Inc. ® 63296 Powell Butte Hwy • Bend, OR 97701 • (541) 318-6060 • Buy-EI.
FL-2 Important Notice ***** Must Read ***** "DO NOT SOLELY RELY ON THE FL-2 TO DETERMINE THE FUEL LEVELS IN THE FUEL TANKS ." The use of the FL-2 does not eliminate or reduce the necessity for the pilot to use good flight TANKS." planning, preflight and in-flight techniques for managing fuel. The following requirements must be met with before operating the aircraft with the FL-2: 1. The FL-2 should only be installed in experimental aircraft or a certified aircraft by a T.C. or S.T.C. holder. 2.
Contents Warranty ................................................................................... 2 Operating Instructions ............................................................ 3 Instrument: ....................................................................................................... Analog Display: ................................................................................................ Digital Display: .......................................................................
Warranty 1209921 Electronics International Inc. warrants this instrument and system components to be free from defects in materials and workmanship for a period of one year from the user invoice date. Electronics International Inc. will repair or replace any item under the terms of this Warranty provided the item is returned to the factory prepaid. l. This Warranty shall not apply to any product that has been repaired or altered by any person other than Electronics International Inc.
Operating Instructions FL-2RA & FL-2CA Instrument: The FL-2 is a fuel level instrument featuring dual 90 degree analog displays and a digital display. These two displays provide the primary indication of the fuel level for the left and right wing tanks and offer many advantages over conventional analog gauges, as described below. The instrument may be calibrated to display in gallons, pounds or liters.
Note: To acknowledge a blinking LED (i.e., to stop the blinking), change the position of the Tank Selector Switch. Once a blinking warning is acknowledged it will not occur again until the FL-2's power has been turned off and back on. Although these blinking warnings are valuable, they can be annoying. For this reason we provide a way of shutting them off. During night operation the analog LED's may be too bright. If so, turn the panel light rheostat up and the analog lights (LED's) will dim.
than the actual fuel in the tanks when the tanks are full. When the fuel level drops to a point where the fuel sensors start to detect a change, the displayed fuel level should be accurate. Check your system by comparing the displayed fuel levels on the FL-2 to the fuel levels listed in the flight manual at each fill up. 3. Low Fuel Readings - Do not rely on the FL-2 to determine the fuel in the tank for indicated tank levels below 1/8.
3. Preflight - Do not rely on the FL-2 to determine the fuel level in the fuel tanks. The pilot must visually check/measure the fuel levels in the tanks before every takeoff. Cross-check the measured fuel levels with the displayed levels on the FL-2. Also, crosscheck these levels with the fuel requirements for the flight listed in your flight plan. 4. In Flight - Make the FL-2 part of your normal instrument scan.
7. The FL-2 must be calibrated to the aircraft fuel system and its accuracy must be verified before flying the aircraft. 8. The FL-2 should only be installed in experimental aircraft or a certified aircraft by a T.C. or S.T.C. holder. 9. A copy of this manual must be presented to the pilot/owner. It contains important information they must read. Route The Circular Connector: Starting from under the instrument panel, route the circular connector wire harness up to the instrument mounting location.
Route the External W arning Control Line: Warning The white/yellow wire can be connected to a relay to control an external light, buzzer, etc. This wire grounds when the red warning light is on. The current in this line must be limited to 2/10 of an amp maximum. Exceeding this limit will damage the unit. If this feature is not used leave this line open. Tie wrap this wire so it does not obstruct the freedom of travel of any controls.
Selecting the Proper Filter: The filter may be programmed for a response time of 8, 16, 32, 64 or 128 seconds (time to 100% respond to a change in the fuel level). The advantage and disadvantage of a fast and slow filter setting is discussed below. Advantages of a faster filter setting (8 to 16 seconds) - A fast response time may show some fluctuations in the fuel level during sloshing or turns. This can give you a good feeling the instrument is working, and there is fuel in the tank.
Programming the Filter Filter,, Operating Mode and Resolution: To program the Filter, Operating Mode and Resolution perform the following steps: Note: You will need access to the back of the FL-2 to program the instrument. This may be difficult with the instrument mounted in the panel. You may want to remove the FL-2 from the panel and reconnect it on the outside of the instrument panel with the wires routed through the instrument mounting hole. Tape a clean rag around the FL-2 case to protect it. 1.
Calibration Issues: The FL-2 must be calibrated to the left and right fuel tanks separately. You may calibrate the FL-2 in gallon, pounds, liters or any other unit you choose. Whatever units you calibrate the FL-2 in, is the units it will display in. For this procedure we will use gallons. The FL-2 can be calibrated for 4 gallon tanks or as large as 999 gallon tanks. The left and right tanks do not have to be the same size or shape.
Calibrate the Left F uel T ank: Fuel Tank: 1. Use the chart at the back of this section and select the fuel levels for each calibration point. You can use any number of cal points between 2 and 9. If you are not sure what the full fuel level will be for your tank, you can record this level at the last step of this procedure when you have an accurate measurement of the fuel required to fill the tank. 2.
Note: If you want to manually program the Sensor Counts, push and hold the Enter Button at the back of the FL-2 (with the Sensor Counts displayed and not blinking) until the thousands digits starts to blink. To increase the count of the blinking digit, move the Selector Switch from the center position to the right. To decrease the count of the blinking digit, move the Selector Switch from the center position to the left. To blink the next digit to the right, tap the Enter Button on the back of the FL-2.
13. Place the Selector Switch into the right position. The FL-2 will display the last programmed Sensor Counts for this cal point. Tap the Enter Button on the back of the FL-2, the display will start blinking and the Sensor Counts for the current fuel level in the tank will be displayed. Wait for the display to stabilize and tap the Enter Button to lock the current sensor counts into the display, and stop the blinking. 1056 14.
Calibrating the Right F uel T ank: Fuel Tank: The right fuel tank is calibrated in the same manner as the left tank. The right tank does not have to be the same size nor does it have to have the same calibration points as the left tank. Calibrate the right tank using the left tank calibration procedure (steps 1 through 15) with the following change: When the procedure calls for the Selector Switch to be placed in the left position, place it in the right position.
FL -2RA-12 and FL -2RA-24 FL-2RA-12 FL-2RA-24 Wiring Diagram Do not use screws longer than 1/2" (4 ea.). 23 Circular Connector Red 3' Power Lead, connects to 12 or 24 Volt Bus via 1 amp fuse or circuit breaker. Black 3' Ground Lead, connects to Ground. White/Brwn White/Red Wire Harness White/Orng White/Yel 3' Backlight Control Line, connects to 12 Volt Bus via 1 amp fuse (may use the power fuse). 12 volts turns on the digital display backlight.
FL-2RA-12 and FL-2RA-24 Circular Connector Connecting Cable Harness, Back View (wire side) 3 6 9 W/ Yel Blk Red 1 W/ Org W/ Red W/ Brn 4 Brwn Orng 7 17 Note: See Wiring Diagram for hook up information.
FL -2CA FL-2CA Wiring Diagram Do not use screws longer than 1/2" (4 ea.). 23 Circular Connector Red 3' Power Lead, connects to 12 or 24 Volt Bus via 1 amp fuse or circuit breaker. Black 3' Ground Lead, connects to Ground. White/Brwn White/Red Wire Harness White/Orng White/Yel 3' Backlight Control Line, connects to 12 Volt Bus via 1 amp fuse (may use the power fuse). 12 volts turns on the digital display backlight.
FL-2CA Circular Connector Connecting Cable Harness, Back View (wire side) 2 6 W/ Org W/ Red 10 14 Red Blk W/ Yel W/ Brn Wht Wht Blk Blk 16 3 Red Red 15 19 Note: See Wiring Diagram for hook up information. 1 7 7 to 9 (Left Fuel Level Input). 11 11 to 13 (Right Fuel Level Input).
Specifications and Operating Features Model: FL-2RA-12 (Dual Fuel Level Instrument to be used in a 12 Volt System and with resistive sensors .) FL-2RA-24 (Dual Fuel Level Instrument to be used in a 24 Volt System and with resistive sensors .) FL-2CA (Dual Fuel Level Instrument for use with E.I.'s capacitive sensors from 125Hz to 5KHz.) Case Size and Weight: 2.5" x 2.5" x 3.65" depth, 2 1/4" Bezel. 10 Oz. Unit Only. Power Requirements: 7.5 to 35 Volts, 1/10 Amp.
Electronics International Inc. ® By: Ron Roberts Technical Notes 0718971A Rev. A: 10/15/01 FL -2 F uel Level Instrument FL-2 Fuel and Fuel Level System Issues Getting a fuel level system to operate accurately is not always an easy task. The FL-2 solves many of the problems found in standard gauges, but there are still many issues that must be addressed. These notes will cover some of those issues.
Technical Notes Page Two 4. As you lower the sensor float slightly from the top of the tank, the resistance should start to increase. If it does not, the sensor resistance is probably bottomed out. The FL-2 will read lower than actual fuel levels until the sensor wiper drops onto the resistive element. With the sensor float held to the top of the tank, adjust the sensor float arm so the wiper is on the resistive element and not on the termination (end stop). You will need an ohmmeter to determine this.
Technical Notes Page Three As a general rule, resistive sensors can be unreliable. We tested a number of NEW resistive fuel sensors and only found two that passed our tests. That was the Stewart Warner F-385-CP05 and the Rochester 7740-304. We do not know the long-term reliability of these sensor. Some problems with resistive fuel sensors are listed below: A. Linearity - This is NOT a problem when used with the FL-2. The FL-2 compensates for sensor and tank non-linearity. C.
Technical Notes Page Four Capacitive and Resistive F uel Level Sensor Issues Fuel The dihedral of the wing can affect full fuel level readings. Once the fuel level in the tank goes above the sensor, the fuel level reading on the FL-2 will not read any higher. (For example: if a tank holds 20 gallons of fuel but at 18 gallons the fuel is at the top of the sensor, the maximum the FL-2 will read is 18 gallons.) The FL-2 reading will only be accurate for tank levels of 18 gallons and lower.
