Fuel gauge

The fuel gauge, also called fuel gauge, fuel gauge or fuel gauge, is to allow an estimation of the remaining for travel available fuel supply. To this end, in view of the driver a display instrument is positioned, the most informed with an analog pointer reading between the marks full and empty, with tick marks for quarter, half and three-quarter filling, usually a red flag for reserve driver. Often a (usually yellow ) lamp is installed in addition, when the fuel supply is completely depleted. The stock can also be displayed in liters.

An analog sensor must be integrated in order to use inside the fuel tank. Previously it was a filled with air, soldered brass float, which was mounted rotatably on an axle. By means of a bell crank was the height of the fuel level mechanically to a Bowden cable to a pointer instrument on the dashboard passed ( VW Beetle of the 60's ).

Today, tanks carry a float tube with a plastic float, whose vertical height is toggled an electrical resistance. This resistance is measured by the meter, and the corresponding level is displayed, for the most part present in the instrument cluster. A common standard size is 240-33 ohm, 240 with full and empty tank at 33. In addition to these passive tank sensors, there are also active tank sensors that output a variable voltage.

Another variant used today measures with flow sensors, the quantities of fuel that can be added and removed and calculates the current level. Since, however, never actually a level is measured, such systems are prone to errors that can not automatically detect the device. So it happens that the sensor on the filler neck does not work with all nozzles and an incorrect or no amount of fuel is measured. The result is that the fuel gauge for the rest of the tank " empty" and it is impossible to estimate when the tank is actually empty.

Only in the rarest cases are analog displays correctly and reliably: either you can set the option " Full" good or point but the display "Empty". The latter is highly recommended because of "full ", the driver remembers the last fill up, "empty " but could get him in trouble. Therefore, the adjustment of the display to " empty" is far more meaningful.

Part refrained from earlier vehicles on a fuel gauge (VW Beetle savings until 1966 ). Instead, was the bottom of the tank outlet a switchable mostly by foot fuel valve mounted (reserve tap): In normal driving, the fuel is discharged from a tube a few centimeters height, then after switching the level is below the tube for a few more kilometers to proceed available. Common spelling mistake here is when refueling to mention the return of the reserve valve: In the next longer driving the car then lay suddenly and without reserve fuel. This tube type is still common today in motorcycles without a fuel gauge.

• Fuel technology
• Display
• Gauge