Yokogawa EXA PH202 2-Wire pH/ORP Analyzer - Manuel (Page 84)

IM 12B6C3-F-E
11-1 Test Certificate
Test
EXA Series
Certificate
Model PH202
Transmitter for pH / ORP
1. Introduction
This inspection procedure applies to the model PH202 converter. There is a serial number, unique to
the instrument, which is stored in non-volatile memory. Each time the converter is powered up, the
serial number is shown in the display. An example is shown below, for details see the Users manual:
Unique Number
Line Number
ATE (automatic test equipment no.)
Month code
Year code
2. General Inspection
Final testing begins with a visual inspection of the unit to ensure that all the relevant parts are present
and correctly fitted.
3. Safety Test
The (-) minus and the external ground terminal of the housing are connected to a Voltage generator
(100 VDC). The measured impedance value should be over 9.5 MΩ.
Terminal 12 and the external ground terminal of the housing are connected to a Voltage generator
(500 VAC RMS) for 1 minute. The leakage current should remain below 8 mA.
4.1 Accuracy Testing
Our automated testing facility checks the accuracy of the dual high inputs of the instrument using a
calibrated variable resistor (decade resistor box) to simulate sensor mV’s.
4.2 Accuracy Testing of all supported temperature elements
Our automated testing facility checks the input accuracy of the instrument using a calibrated variable
resistor (decade resistor box) to simulate the resistance of all temperature elements.
11. Test Certificate
025
F70.00