TX800 SERIES INSTRUCTIONS
Seametrics • 253.872.0284 • www.seametrics.com
Page 10
OPERATION AND MAINTENANCE
Calibration (“K-factor”)
The K-factor represents the actual number of pulses per gallon
the meter produces during a ow test. This number can be
entered into your electronic control to make it read properly.
If the TX800-Series meter is ordered with a tee tting, it is
factory-calibrated in the tting and the K-factor is indicated
on the side of the tting. For saddle and weldolet K-factors,
see the K-factor calculator located at the bottom of the www.
seametrics.com home page.
Find Your K-Factory Here
10031295
MF81T-P200
K: 53.6
Modularity
Any of the TX800-Series ow sensors can have electronic
modules mounted directly to them, either at the time of order
or by adding an adaptor kit in the eld (part number 102632).
Alternatively, the ow sensor and indicator or transmitter can
be installed remote from each other. The FT420 is an indicating
transmitter (rate, total, 4-20 mA output), and the AO55 is a
blind 4-20 mA transmitter. For data logging, add the DL76. The
FT520, which provides batching and other functions, is suitable
for remote installation.
Output
The output is a current-sinking pulse (square wave) compatible
with many controls in addition to the Seametrics indicators and
transmitters. The most common of these are water treatment
controllers and programmable logic controllers (PLC’s). For
these units, it is sometimes necessary to provide a pull-up
resistor if the controller does not provide for a current-sinking
output. (See the section on “Connecting to PLC’s and other
controllers” before connecting to a non-Seametrics control.)
Fittings
Since the TX800-Series sensors are not adjustable, they must
be purchased with ttings appropriate to the application. The
TX81x is sized for ttings of 1 1/2” to 3”. The TX82x is for ttings
of 4” and 8”. Each tting insures that the ow sensor is installed
at the correct point. Every ow sensor and every tee tting is
wet calibrated. Saddle ttings are normally not wet calibrated,
because they are eld-installed on a pipe. In PVC however it is
possible to order a saddle pre-installed on a standard length of
pipe, in which case the entire assembly is wet-calibrated. For
all other saddles, the K-factor (pulses per gallon) is established
through testing with various standard schedules of pipe and
provided with the saddle.
Minimum Flow
As with any other ow sensor, there is a rate below which the
TX800-Series sensor cannot read. Check the ow rate table
below for the minimum ow rate detectable by the sensor for
a given pipe size.
1½” 2” 3” 4” 6” 8”
Min 2.8 5 11.5 19.8 45 78
Max 190 314 691 1190 2700 4680
Flow Rate (Gallons per Minute) Flow Rate (Liters per Minute)
1½” 2” 3” 4” 6” 8”
Min 10.60 18.93 43.53 74.95 170.34 295.26
Max 719.23 1189 2616 4505 10221 17716
