Step 1: Inspecting The Application; Step 2: Performing A Zero Point Adjustment; Step 3: Calculating The Measurement Error - Siemens SITRANS F Operating Instructions Manual

Troubleshooting/FAQs
11.2 Troubleshooting sensor-related problems
11.2.1

Step 1: Inspecting the application

Ensure that:
1. The sensor is installed as described in "Installing/mounting" (Page 35).
2. The sensor is located in a vibration-free position. Vibrations can disturb the sensor and
Depending on application, you should furthermore ensure the following:
● Liquid application
● Gas application
11.2.2

Step 2: Performing a zero point adjustment

The second step in the troubleshooting procedure is to zero point adjust the device. For
further information on zero point adjustment, see "Commissioning" (Page 69).
11.2.3

Step 3: Calculating the measurement error

The result of the zero point adjustment will show you if the zero point was set under good
and stable conditions.
The lower the obtained value of the parameter "Zero Point Standard Deviation", the lower is
the achievable measuring error. For a well-installed flowmeter, the Zero Point Standard
Deviation corresponds to the specified zero point stability for the sensor size, see
"Performance (Page 165).
The parameter "Zero Point Standard Deviation" is located in the "Maintenance &
Diagnostics" menu in the SIMATIC PDM.
158
therefore cause measurement error.
Ensure that the sensor is filled with liquid and liquid only.
Air or gas bubbles in the liquid cause instability and can result in measurement errors.
Flush the pipe systems and the sensor for several minutes at maximum flowrate to
remove any air bubbles which may be present.
NOTICE
The liquid must be homogeneous in order to measure with high accuracy. If the liquid
contains solid particles of greater density than the liquid, then these solids can settle,
especially at low flow rates, which will cause instability in the sensor and lead to
measurement errors.
Ensure that the gas pressure/temperature conditions contain sufficient superheat to
prevent dewing or precipitation. If the gas contains vapor or droplets then these may
precipitate, causing instability.
SITRANS FC430 with HART
Operating Instructions, 03/2012, A5E03361511-01