Metrohm 726 Titroprocessor - Manual (Page 291)

13. Appendix
726 Titroprocessor, Instructions for use 285 285
Measurement group 1 or 2 (option) measurement groups each with
• 2 high-impedance measurement inputs for pH, redox, ISE sensors
• 1 input for separate reference electrode
• The above inputs also serve as a differential amplifier
• 1 measurement input for polarized electrodes
• 1 measurement input for Pt 1000 or Pt 100 temperature sensors, with
automatic recognition
• 1 polarizer
•• 2 parallel deltasigma A/D-converters, 20 bit, 50 ms sampling rate
•• 1 stirrer connector (see above)
Electrical insulation
All interface signals are referred to a common reference potential. The refer-
ence source is electrically insulated from the main circuit. Each measure-
ment interface is insulated individually as well.
The electrical insulation is due to the measuring technique. It does not
comply with certain security specifications.
Measurement ranges Potentiometric –2500 mV…2500 mV
pH–20.000…20.000
Amperometric –250 µA…250 µA (Upol)
Voltametric –2500 mV…2500 mV (Ipol)
Temperature –150 °C…450 °C
Measuring inaccuracy Limits Inputs Abs. error Resolution
Ind A1, A2, B1, B2 ≤ ± 0.8 mV 5 µ V
Diff A, Diff B ≤ ± 4.0 mV 5 µ V
Pol ( µ A, Upol) ≤ ± 3 µ A 0.001 µ A
Pol (mV, Ipol) ≤ ± 20 mV 5 µ V
Pt100/1000
0°C…100°C
≤ ± 0.3°C 0.005°C
Reference conditions
The measurement error limits are guaranteed at works, measured at an
ambient temperature of 25°C (± 5°C) after 5 min. operating time.
The error limit of the temperature measurement applies to the socket con-
tact resistance as well as to the sensor cable of the Metrohm (6.1103.0000)
Pt100 Temperature Sensor. It does not consider the sensor inaccuracy.
Polarizer source Polarizer voltage (Upol)
accuracy Range -1270 mV…1270 mV
Linearity ≤ ± 20.0 mV
Resolution 10.0 mV
Polarizer current (Ipol)
Range
-127 µ A…127 µ A
Linearity ≤ ± 3.0 µ A
Resolution 1.0 µ A