Capacitance-based liquid-level senders are the smart choice where ruggedness is key.


Centroid fuel senders determine fuel level by measuring the capacitance between their metal inner and outer tubes.  Capacitance increases as liquid replaces air between the tubes.  No float is required.  They are designed for non-conducting liquids only: oil, diesel, and gasoline with up to 10% ethanol.


Centroid’s potable-water senders measure the capacitance between water and the inner conductor of a Teflon-jacketed sense wire, inside a PVC tube.  This capacitance increases with water height.  Non-potable water (wastewater, saltwater, rusty water) can leave a coating on the sense wire which keeps the reading from dropping to Empty correctly. So we only sell the water senders for potable water.


Electronics in the sender’s head convert capacitance into resistance, voltage, or milliamps, as determined by which output is ordered.  Typically the electronics are powered by an ignition voltage connection.  For some brands of E240/F33 ohm needle gauge, a sender can be provided that runs the electronics from the Send voltage.



Centroid Products, Inc is located at 2104 Hibiscus Dr, Edgewater  FL 32141.  We have been selling senders to manufacturers, military, and individuals since 1983.  We have 11 employees and currently manufacture and sell about 25,000 senders per year.



Orders and prices: call Mary at 386-423-3574 between 8a-2p EST Mon/THU   For preparation please first see the Ordering Guide, below.


Tech Support:   


We have found phone to be less effective than written test procedures.  So we do tech support by email only.  You’ll get emailed assistance from an engineer the same business day.






Ordering Guide


Bend Template for senders bent by the factory


Mounting styles




2-year Warranty



Installation and Calibration for programmable senders (CGFP, CGWP)


Installation and Calibration for old-style senders (CGF, CGW)



Troubleshooting in general


Troubleshooting for CompuTank installations


Troubleshooting for Monaco installations


Mastercraft and Moeller information




Other:   Parker ‘FS’ senders (now via FTG, Inc)


Other:   Alternatives to CompuTank displays