Metrohm 867 pH Module - Manual (Page 42)

7.1 Measuring interface
￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
34 ￭￭￭￭￭￭￭￭
867 pH Module
7 Technical specifications
7.1 Measuring interface
The 867 pH Module has one galvanically isolated measuring interface.
The measuring cycle is 100 ms for all measuring modes.
7.1.1 Potentiometry
One high-ohm measuring input (Ind.) for pH, metal or ion-selective elec-
trodes and one measuring input (Ref.) for separate reference electrodes.
Input resistance > 1 · 10 12 Ω
Offset current < 1 · 10 –12 A (under reference conditions)
Measuring mode
pH
Measuring
range –13 - +20 pH
Resolution 0.001 pH
Measuring
accuracy ±0.003 pH
(±1 digit, without sensor error, under reference conditions)
Measuring mode
U
Measuring
range –1,200 - +1,200 mV
Resolution 0.1 mV
Measuring
accuracy ±0.2 mV
(±1 digit, without sensor error, under reference conditions)
Measuring mode
Conc
Measuring
range 10 –21 - 10 20
Resolution
Measuring
accuracy
(±1 digit, without sensor error, under reference conditions)