
JF-1A CONDUCTIVITY SENSOR
A440-009 Page 5 of 56
FEBRUARY 2009
2.0 USAGE
Fuel products such as jet aviation and diesel fuels that are transferred at high pumping
rates may develop a static electrical charge due to the very lo conductance of the
fluid. The D-2 JF-1A Conductivity Meter measures the ability of the fuel to dissipate
that charge. The conductivity of aviation fuels is purposely increased using additives
that reduce the ability of the fuel to store static charge. These additives are normally
injected prior to transfer to the load vessel. The D-2 JF-1A Conductivity Sensor has the
ability to monitor the electrical conductivity of fuel continuously, allo ing its use as a
sensing element in an automated additive injection system. The D-2 JF-1A ability to
measure ith high precision continuously at a high sampling rate (1 hertz) allo s for
precision control of additive injection. The industrial standard 4-20 mA sensor allo s for
its use ith industry standard PID Controller/Display units combined ith additive
injector pumps to provide real-time control over addition of conductivity-enhancing
additives during the transfer process. The Digital Signal Processing (DSP) full numerical
compensation of conductivity for fuel temperature allo s the system to be used in
facilities independent of a ide range of ambient temperatures. The D-2 JF-1A provides
consistent results independent of temperature ( hen temperature compensation is
enabled). Optionally a second 2 Wire (4 – 20 mA) temperature output interface is
available.
3.0 FUNCTION
The D-2 JF-1A Conductivity Meter reads conductivity in picosiemens/meter, fuel
temperature in ITS-90 degrees C, and fully compensated Conductivity in picosiemens/
meter per ASTM D 2624, Appendix X2. These measures are equivalent to CU or
Conductivity Units. The sensor can be used in a 2 ire 4-20 mA industrial control loop
or in conjunction ith a serial input device using RS-232 IEEE Standard ASCII Serial
Input Data. Optionally a 2 ire (4-20 mA) temperature interface can be added to allo
remote monitoring of fuel temperature.