82
Reference Manual
00809-0100-4026, Rev HA
Section 5: Basic Configuration/Start-up
November 2014
Basic Configuration/Start-up
Freeze Current: the output current is set to the last valid value at the time when the error
occurs.
Default settings for alarm mode:
Measurement errors: Output current = High
Measured value out of range: transmitter enters saturation mode (if Limit Alarm is
disabled)
Table 5-2. Analog Output: Standard Alarm Value vs. Saturation Value
In saturation mode, if the primary variable is not in low alarm mode, the minimum output is 3.9
mA. If the primary variable is not in high alarm mode, the maximum output is 20.8 mA.
Table 5-3. Analog Output: NAMUR-compliant Alarm Value vs. Saturation Value
5.3.6 Level and distance calibration
Level and distance calibration may be necessary when using a nozzle or pipe or if there are
disturbances in the near zone caused by a physical object.
Non-metallic (e.g. plastic) vessels and installation geometry may introduce an offset for the zero
reference point. This offset may be up to ± 25 mm. The offset can be compensated for using
Distance Calibration.
When calibrating the transmitter, it is important that the product surface is calm and that the
tank is not being filled or emptied.
A complete calibration is performed in two steps:
1. Calibrate the distance measurement by adjusting the Calibration Offset parameter.
2. Calibrate the level measurement by adjusting the Tank Height.
Level 4–20 mA saturation value 4–20 mA alarm value
Low 3.9 mA 3.75 mA
High 20.8 mA 21.75 mA
Level 4–20 mA saturation value 4–20 mA alarm value
High 20.5 mA 22.5 mA
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