Metrohm 904 Titrando - Manual (Page 48)

9.1 Measuring interface
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904 Titrando
9 Technical specifications
9.1 Measuring interface
Depending on the version, the 904 Titrando has one (version 2.904.0010)
or two (version 2.904.0020) galvanically isolated measuring interface(s).
The measuring cycle is 100 ms for all measuring modes.
9.1.1 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)
9.1.2 Temperature
A measuring input (Temp.) for temperature sensors of the Pt1000 or NTC
type with automatic temperature compensation.
R (25 °C) and B value can be configured for NTC sensors.
Measuring range
Pt1000 –150 - +250 °C
NTC –5 - +250 °C
(R (25 °C) = 30,000
Ω and B (25/50) = 4,100 K)