JF-1A Conductivity Sensor
A440-009
Page 20 of 56
FEBRUARY 2009
Fuel with Additive Per ASTM
N
The
Number
of
Samples
of
Conductivity Box Car Averaged See
Section 13.0
NREF
The number of Reference Channels
Averaged
DAO
The 4-20 mA output offset counts
to trim current to 4.0 mA at Zero
Conductivity
DAF
The 4-20 mA full Scale in pS/M for
an load current of 20 mA Total
W
Anti Spike Filter Maximum Scan-
Scan Change in pS/M
Any constant can be read individually by entering the reference name followed
by a <CR>. Any constant can be set by entering the reference followed by an
equal’s sign and then the new value to be entered. All constants can be stored
in non-volatile memory using the ***E command. Note, cycling power after
changing constants and before storing them in non-volatile memory using the
***E command will result in the unit reverting to the original values stored.
To return to run mode, issue the ***R command or cycle power.
Current Loop Output Testing
The JF-1A, while in OPEN MODE, can temporarily output a current equal to a
given conductivity reading for system testing. To output a current equal to a
given conductivity, as example 250 pS/M, while in OPEN MODE issue the
command COND=250. This command will configure the output to draw current
equal to a reading of 250 pS/M, or on a 0 – 500 pS/M configured sensor 12
milliamps. Readings and output currents for various range configured units is
given in the table below. (Note, the JF-1A is normally configured for a 0 – 500
pS/M range equating to a 4 – 20 mA current range.)