
4690 Series
Turbidity systems
8 Configuration and Electrical Calibration
32
IM/4690–EN Rev. A
8.6 Electrical Calibration
8.6.1 Equipment Required
1. Millivolt source: 0 to 4000 mV.
2. Digital milliammeter (current output measurement): 0 to 20 mA.
8.6.2 Preparation
1. Isolate the analyzer and turbidity sensor from the power supply and disconnect the sensor and current output from the
analyzer's terminal block – see Fig. 4.4, page 14 (wall-/pipe-mount analyzer) or Fig. 4.5, page 15 (panel-mount analyzer).
2.
Wall- / Pipe-mount Analyzer
a. Connect the millivolt source '+' and '–' to terminals 4 and 7 respectively.
b. Connect the milliammeter to the retransmission output terminals.
c. Ensure the earth on the millivolt source is connected to the earth stud.
Panel-mount Analyzer
a. Connect the millivolt source '+' and '-' to terminals 9 and 6 respectively.
b. Connect the milliammeter to the retransmission output terminals.
c. Ensure the earth on the millivolt source is connected to the earth stud.
3. Switch on the supply and allow ten minutes for the circuits to stabilize.
4. Select
ELECTRICAL CAL
page and proceed as in Section 8.6.3, following.
Caution.
The analyzer is calibrated by the Company prior to despatch and an electrical calibration should not be necessary. If an
electrical calibration is carried out, suitably calibrated and verifiable test equipment must be used.