Low Flow Cut-Off - Siemens SITRANS F MASS 2100 Operating Instructions Manual

Parameter assignment FCT010
8.1 Functions
Zero point standard deviation
After completion of the procedure, the standard deviation is calculated in accordance with the
following formula:
Zero point standard deviation
Standard deviation of N values
The standard deviation contains important feedback on the homogeneity of the fluid, for
example on the presence of bubbles or particles.
The standard deviation must be within the determined Standard deviation limit (Modbus
address 2138).
Note
Exceeded standard deviation limit
If the standard deviation is greater than the configured limit, proceed as follows:
• Check that the tube is completely filled and that the flow rate is absolute zero.
• Check that the installation is vibration-free.
• Check the validity of the configure Standard deviation limit (Modbus address 2138).
• Repeat the zero point adjustment.
Successful automatic zero point adjustment
If the new zero point offset value is valid, it is automatically stored as the new zero point for the
sensor. It remains stored in the case of a power failure.
Manual zero point adjustment
In case an automatic zero point adjustment cannot be performed, it is possible to do a manual
zero point adjustment by entering the zero point offset value.
1. Select Modbus address 2132 Zero Point Adjustment and set the value to 1 = Manual Zero
Point Adjustment.
2. Select Modbus address 2133 Manual Zero Point Offset and enter the desired offset value.
8.1.3

Low flow cut-off

In certain applications, for example dosing applications, no flow signals under a certain flow
level are desired. In these applications, the flow signal can be forced to zero when the flow is
lower than a predefined flow value (low flow cut-off).
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SITRANS MASS 2100 & FC300 (FCT010/DSL)
Operating Instructions, 06/2020, A5E39788682-AB