Automatic Recognition of Pre-Selected Buffer Values
Diagnostic Error Messages
Surface Mount, NEMA 4X Enclosure
Isolated
产品描述
The PHTX-692 and ORTX-692 have been discontinued. Please see the PHTX-271 as a possible substitute or contact our
Flow and Environmental department.
For accurate measurements of pH and
ORP, the model PHTX-692 and
ORTX-692 transmitters provide local
indication as well as a 4-20 mA output.
The large PHTX-692 LCD can alternately
indicate pH, temperature, the sensor’s
millivolt signal or the 4-20 mA output. The
ORTX-692 measures ORP and provides a
similar indication, except for pH. Each
model requires only two wires, common
for both output and power. No special
cables are necessary. The isolated, dc
current loop output features high noise
immunity, permitting use of a simple
twisted pair of wires. A single dc voltage
power source can power multiple
transmitters. The PHTX-692 uses either a
1000 ohm RTD or 300 ohm thermistor for
automatic temperature compensation.
Compatible sensors are described in this
section.
When calibrating and configuring the
instrument, clear, easily understood
procedure messages will prompt the
operator. Preprogrammed diagnostic
messages flash automatically if system
operating problems occur.
The isolated 4-20 mA instrument output
eliminates problems caused by electrical
interference. An output hold function can
maintain the output during calibration or
while configuring the instrument. A range
expand feature allows the 4-20 mA output
to represent a single pH unit or larger
segment of the measuring scale (50 mV
for model ORTX-692).
Both models are simple to operate. Using
a watertight keypad, an operator
configures and calibrates the system, and
displays measurement data, without
having to open the enclosure door.
