Gauge will only read 1/2.
I set the sender myself. 30 ohms. 30 ohm gauge. For full deflection when at top of tank and o when at bottom of tank. I did not measure with ohmmeter befofe install.. I did move the tank around to listen for movement though. 12V system.
Its annoying. It acts as though 1/2 is the full mark.
I suppose I 'll have to take it apart this winter.