OEM OPM223, Руководство по эксплуатации

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OPM223/253 Commissioning
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6 Commissioning
6.1 Things to note when commissioning ISFET sensors
Switch-on behaviour
A control circuit is created when the measuring system is switched on. During this time
(approx. 5 ... 8 minutes), the measured value adjusts to the real value. This settling behaviour
occurs every time the liquid film between the pH-sensitive semi-conductor and the reference
lead is interrupted (e.g. caused by dry storage or intensive cleaning with compressed air). The
settling time depends on the length of the interruption.
Sensitivity to light
Like all semi-conductor elements, the ISFET chip is sensitive to light (measured value
fluctuations). However, this only affects the measured value if the sensor is directly exposed
to sunlight. For this reason, avoid direct sunlight when calibrating. Normal ambient light does
not have any effect on the measurement.
6.2 Function check
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Warning!
• Check all connections for correctness.
• Make sure that the supply voltage is identical to the voltage written on the nameplate!
6.3 Switching on
Familiarise yourself with the operation of the transmitter before it is first switched on. Please
refer in particular to the "Safety instructions" and "Operation" sections.
After power-up, the device performs a self-test and then goes to the measuring mode.
Now calibrate the sensor in accordance with the instructions in the "Calibration" section.
!
Note!
During commissioning, the sensors must be calibrated so that the measuring system can
return precise measurement data.
Then perform the first configuration in accordance with the instructions in the "Quick start-up"
section. The values set by the user are kept even in the event of a power failure.
The following function groups are available in the transmitter (the groups only available in the
Plus Package are marked accordingly in the functional description):
Setup mode
• SETUP 1 (A)
• SETUP 2 (B)
• CURRENT INPUT (Z)
• CURRENT OUTPUT (O)
• ALARM (F)
• CHECK (P)
• RELAY (R)
• SERVICE (S)
• SERVICE 2 (E)
Calibration and offset mode
• CALIBRATION (C)
• NUMERIC (N)
• OFFSET (V)
!
Note!
A detailed explanation of the function groups available in the transmitter can be found in the
"System configuration" section.