Yokogawa SC24V Differential pH ORP Electrode - Manual (Page 8)

IM 12B6J7-02E-E
8
2 GENERAL SPECIFICATIONS
2.1 Measuring elements : pH glass electrode
Sodium glass electrode
Solid Platinum electrode
Pt1000 temperature sensor
2.2 Wetted parts Measuring sensor : Glass
Earth pin : Solid Platinum
2.3 Functional specifications (at 25°C)
Isothermal point : pH 7, pNa 0
Reference system : pNa, salt sensitive reference glass
Glass impedance - pH : 750 MΩ nominal
- pNa : 750 MΩ nominal
Temperature element : Pt1000 to IEC 751
Asymmetry potential (zero) : 0 ± 15 mV
Slope : > 90 % (of theoretical value)
Note: The SC24V temperature sensor is designed for cell compensation and for indication.
It is NOT designed for process temperature control.
2.4 Dynamic specifications
Response time pH : t
90
< 15 sec. (for 7 to 4 pH step)
Response time temperature : t
90
< 1.5 min. (for 10 °C step)
Stabilization time pH : < 2 min. (for 0.02 pH unit during 10 sec.)
2.5 Operating range
pH : 2 to 14 (refer to Table 3)
Temperature : 10 ºC to 120 °C (50 ºF to 248 °F)
Pressure : 0 to 10 bar (0 to 142 PSIG)
Conductivity : > 50 µS/cm
Table 3: pH operating range as function of the ionic strength (pH≥pNa+2)
pNa Ionic strength [mol ion+ per liter] pH operating range
0 1 2 to 14
1 0.1 3 to 14
2 0.01 4 to 14
3 0.001 5 to 14
4 0.0001 6 to 14
Note: The pH operating range is given at room temperature, but at high process temperatures the
lifetime of the sensor will be seriously shortened. For pH values > 12 the accuracy of the pH
measurement will change significantly by the alkali error.