YOKOGAWA FLXA21 User Manual

<5. CALIBRATION OF pH/ORP>
5-5
IM 12A01A02-01E 8th Edition : Oct. 01, 2015-00
5.1.3 Sample calibration
A sample calibration is a single-point calibration for only the zero (asymmetric). It adjusts the
recorded reading to a collected sample value. Press [Take Sample] to record a collected sample
value in memory. Re-enter the Sample Cal. screen and press [Start calibration] to perform a
sample calibration. This updates the recorded data.
NOTE
When a sensor or an electrode is exchanged or replaced, sensor wellness data should be reset.
When a sensor is replaced, the replacement can be recorded manually into a logbook. (Refer to
the gure 3.9.)
5.2 Temperature calibration
For the most accurate measurements, it is important to have a precise temperature
measurement. Measure the temperature with a high-precision thermometer and adjust the
sensor reading accordingly. For best accuracy, this should be done as near to the normal
operating temperature as possible.
5.3 ORP calibration (rH calibration)
The calibration modes for ORP or rH are “Manual” and “Sample”. No automatic calibration
feature is available in an ORP or rH calibration.
Calibration is performed stepwise. Follow the prompts displayed on the screen.
A stability check is made at each measurement point. Proceed to the next step only after the
reading has stabilized.
NOTE
When a sensor or an electrode is exchanged or replaced, sensor wellness data should be reset.
When a sensor is replaced, the replacement can be recorded manually into a logbook. (Refer to
the gure 3.9.)
PH
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YOKOGAWA FLXA21 Specifications

General

Display	LCD with backlight
Material	Polycarbonate
Measurement	pH, ORP, Conductivity, Dissolved Oxygen
Measurement Principle	Electrochemical
Measurement Range	Varies based on sensor type
Accuracy	Varies depending on the sensor and measurement type. Refer to the specific sensor datasheet.
Temperature Compensation	Automatic
Inputs	temperature input
Outputs	Two 4-20 mA outputs, HART communication
Communication	HART
Power Supply	24 V DC
Operating Temperature	0 to 50 °C
Process Temperature	Varies depending on the sensor. Refer to the specific sensor datasheet.
Process Pressure	Varies depending on the sensor. Refer to the specific sensor datasheet.
Protection Rating	IP66/67, NEMA 4X
Enclosure Rating	NEMA 4X