Manual

OPERATION
Page 6
Flow Range (GPM)
1-1/2" 2" 3" 4" 6" 8"
Min 1.1 2.1 4.6 7.9 18 31
Max 190 314 691 1190 2700 4680
Minimum Flow. As with any other ow sensor, there is a rate
below which the TX80-Series sensor cannot read. Check the
ow rate table below for the minimum ow rate detectable by
the sensor for a given pipe size.
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 TX80-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.
10031295
MF81T-P200
K: 53.6
Find Your K-Factor Here
Modularity. Any of the TX80-Series ow sensors can have elec-
tronic modules mounted directly to them, either at the time
of order or by adding an adaptor kit in the eld (part number
MK10). Alternatively, the ow sensor and indicator or transmit-
ter 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 func-
tions, 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 control-
lers (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-Sea-
metrics control.)
Fittings. Since the TX80-Series sensors are not adjustable,
they must be purchased with ttings appropriate to the appli-
cation. The TX81 is sized for ttings of 1 1/2” to 3”. The TX82
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.