Wednesday, June 19, 2013

Manual for new universal LED Fuel Gauge from Belite Electronics

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Specifications & Installation Instructions for universal LED Fuel Gauge from Belite Electronics

LED Fuel Gauge from Belite Electronics.  Dual tank version also available.
Part Numbers:


See the video explaining it here:

At A Glance:

·         Lightest Weight
·         Smallest Size
·         Best visibility of any fuel gauge
·         LED colors: green, then yellow, then red, and also increases in brightness as fuel level goes down
·         Bottom LED flashes brilliant red when out of fuel
·         Single or Dual tank versions
·         Compatible with Capacitive (0-5v) and Resistive Fuel Probe Senders
·         May be calibrated to any individual Fuel Probe Sender
·         Dimmable

Belite’s Improved LED Fuel Gauge provides a LED display which shows the current amount of fuel in your fuel tank.  Calibrated from 0% to 100%, it features unusually bright LEDs which are completely readable in direct sunlight.  It is available in a single or dual version, for support of one or two fuel tanks.  The input compatibility is selectable between traditional float style fuel senders and newer style capacitive fuel senders.  It may be calibrated to match the full and empty point of any fuel sender / tank at the push of a button.  The unit uses digital electronics to interpret, calibrate and display the fuel tank level.  Calibration of the fuel level is done via a single button for each tank.


·        Dimensions:  2 3/8” x 2 3/8” x 5/8” (not including connector height).  Fits standard 2 ¼” instrument hole.  Including connector, complete depth of instrument is 1.0”.
·         Power Supply:  Attaches to any DC power supply between 8 and 14 volts.  Alternatively, you may use LITHIUM 9V batteries.  DO NOT USE ALKALINE 9V batteries.  Battery life is approximately 4 – 8 hours using a lithium 9V battery.
·         Power Consumption:  less than 30ma for single display; less than 50ma for dual display.
·         Weight:  1.2 ounce / 35 grams (includes electrical connector).
·         Color LED Range:  Green (full), Yellow and Red (empty).
·         Probe Compatibility:  Use with any capacitive probe (standard 0-5v output); use with any resistive probe (EG:  30 – 240 ohm; will also work with any other ohm range such as 40 – 90 ohm)
·         Slosh Damping:  Electronic filtering built into the Belite Fuel Gauge controls minor errant reading due to fuel sloshing.
·         FCC Part 15:  Compliant by EXEMPTION, Section 15.103(a)
·         Internal Fusing:  None, use external fuse <= 1A.
·         Power:  use external switching.
·         Power On Self Test:  Observe all LEDs illuminated through pattern check and variable brightness check.
·         Dimming Control:  0 – 12V; 0 = full bright; 12V = full dim.  Use external 5K potentiometer.  Dimming the LEDs substantially reduces power consumption.
·         TSO/PMA:  No.  For use in non-certified aircraft.
·         Warranty:  US:  1 year.  Rest of world:  2 year.
·         Temperature Range:  -20C – 45C (operating).  -40C – 70C (nonoperating).
·         Humidity:  Non-condensing.
·         Cabling:  Black = ground; Red = 8-14v; Yellow = Dimming (leave unconnected if unused).  Remaining wires are for left / right fuel sender input.


Install in any 2 ¼” instrument hole using provided screws and lock nuts.

Attach ground and power to black and red wires by cutting off the 9V connector.  The supplied 9V battery connector may be used for temporary unit testing, or may be used as a permanent source of power.  Use only Lithium 9V batteries.  Walmart sells them, as do many other battery retailers.  They are usually found in the photo section of the store.

If you have decided to install a dimmer, attach the yellow wire to the middle lug of a 5K potentiometer.  The other lugs of the potentiometer must be attached to ground and +12V.  (Using +9V for the dimming potentiometer will not provide full dimming.)

When you turn the fuel gauge on, it will perform a Power On Self Test.  If the LEDs light up from bottom to top, your unit is configured for capacitive fuel senders.  If the LEDs light up from top to bottom, your unit is configured for resistive fuel senders.

To reverse, attach the switch assembly to the program connector, and depress the switch before you power the unit up.  The fuel gauge will sense this condition and permanently reconfigure the gauge form capacitive to resistive, or vice versa.  (Each side [left tank / right tank] of the display gauge has an independent switch.)
We recommend ‘playing’ with this capability before you install the fuel gauge in your airplane.

You MUST have the correct configuration set in your fuel gauge (relative to your type of fuel sender) or you will have improper operation.

The remaining one or two wires are attached to the capacitive fuel senders.  (You may verify the right / left wires by touching them briefly to the positive 9V battery post.)  After verification of right / left, the gauge may be attached to the fuel senders.  Each capacitive fuel sender has an ‘output’ that supplies a voltage indication of the fuel tank level, 0 – 5 volts.  This voltage level is interpreted by the LED fuel gauge to show the amount of fuel in your tank.  Just connect the fuel sender to the fuel gauge and it will work.

Capacitive Probe Fuel Tank Wiring Diagram.  Figure 1.

The remaining one or two wires are attached to the resistive fuel sender.  Additionally, you must attach a 330 ohm resistor (included) from +12V (your system power) to the same line. 

Resistive probe fuel tank wiring.  Figure 2.

Calibration is easy.  Each side of the gauge is calibrated independently.  Calibration is performed AFTER you’ve selected fuel sender type (capacitive vs resistive) and after you’ve attached the senders.

You must have the switch assembly attached to the fuel gauge.

When the fuel tank condition is empty, depress the switch for less than one second.  The fuel gauge will permanently remember this level as being the empty level.

When the fuel tank condition is full, depress the switch for more than three seconds.  The fuel gauge will permanently remember this level as being the full level.

Calibration for each tank is done independently.

The fuel gauge will retain these calibration levels in permanent flash memory storage within the fuel gauge.
After calibration, the switch assembly should be disconnected from the fuel gauge.


We strongly recommend ‘playing’ with the unit prior to installation in your aircraft.  Sender type should be set and verified.  Operation of the LED scale may be verified simply by brushing the input wire against a positive voltage source.  You’ll see the LED jump up and then slowly dissipate down.  If the unit is configured for capacitive senders, a positive voltage will cause the LED indication to rise.  If configured for resistive senders, a positive voltage will cause the LED indication to fall.

It is much easier to resolve issues prior to installing the probes in your aircraft.

Contact us if you have any questions.