TM 10-3930-653-14&P TANK UNIT AND FUEL METER The tank unit is designed to convert the remaining fuel amount into electric current.  See Fig 4-115.  For this purpose, a variable resistor with Nichrome wire is used and the sliding element is linked with the float.  As the float moves up and down, resistance is changed so that the amount of electric current passing across the resistor is also changed. The fuel meter is a bimetal type and its pointer swings depending on the amount of electric current passing through the heating unit of bimetal.  When the float is at  the  highest  position,  resistance  of  the  tank  unit  is  approximately  0.5  to 11W.  This will allow much electric current to flow, so the bimetal crooks largely, causing the fuel meter pointer to swing into  the  lowest  part.    On  the  other  hand,  as  the  fuel  level  lowers  and  the  float  goes  down,  resistance  is  increased,  so electric current is reduced, causing the pointer to swing to the "E" side. Fig. 4-115. 4-64