Flowmeter Calibration and traceability

To ensure continuous accurate measurement, flowmeters must be calibrated. The calibration is conducted at Siemens flow facilities with traceable instruments referring directly to the physical unit of measurement according to the International System of Units (SI).

Therefore, the calibration certificate ensures recognition of the test results worldwide, including the US (NIST traceability).

Siemens offers accredited calibrations assured to ISO 17025 in the flow range from 0.0001 m?/h to 10 000 m?/h.

The calibration follows the ISO 4185 performing calibrations under two methods: Static Weighing and Reference meter. Providing a measurement uncertainty of ±0.1 %.

Siemens Flow Instruments accredited laboratories are recognized by ILAC MRA (International Laboratory Accreditation Corporation - Mutual Recognition Arrangement) ensuring international traceability and recognition of the test results worldwide.

A calibration certificate is shipped with every sensor and calibration data are stored in the SENSORPROM memory unit.

Flowmeter uncertainty

Calibration reference conditions

Technical specifications PROFIBUS PA/DP

Electrical specification DP

Electrical specification PA

PROFIBUS parameter support

The following parameters are accessible using a MS0 relationship from a Class 1 Master.
MS0 specifies cyclic Data Exchange between a Master and a Slave.

¹⁾ Value returned is dependent on the BATCH function.

When ON, Batch progress is returned.

When OFF, TOTALIZER 2 is returned.

Flow and speed chart

Metric

Sizing table (DN 2 … DN 2000)

The table shows the relationship between flow velocity v, flow quantity Q and sensor dimension DN.

Guidelines for selection of sensor

Min. measuring range: 0 … 0.25 m/s

Max. measuring range: 0 … 10 m/s

Normally the sensor size is selected so that nominal flow velocity v lies within the measuring range 1 to 3 m/s.

Example:

Flow quantity of 50 m³/h and a sensor dimension of DN 80 gives a flow velocity of 2.7 m/s, which is within the recommended measuring range of 1 to 3 m/s.

Link to "Sizing program":
https://pia.khe.siemens.com/index.aspx?nr=11501

Imperial

Sizing table (1/12" … 78")

The table shows the relationship between flow velocity v, flow quantity Q and sensor dimension size.

Guidelines for selection of sensor

Min. measuring range: 0 … 0.8 ft/s

Max. measuring range: 0 … 33 ft/s

Normally the sensor size is selected so that nominal flow velocity v lies within the measuring range 3 to 10 ft/s.

Example:

Flow quantity of 500 GPM and a sensor dimension of 6" gives a flow velocity of 5.6 ft/s, which is within the recommended measuring range of 3 to 10 ft/s.

Link to "Sizing program":
https://pia.khe.siemens.com/index.aspx?nr=11501

Installation conditions

Vibrations

Strong vibrations should be avoided.

In applications with strong vibrations, remote mounting of the transmitter is recommended.

The sensor must always be completely filled with liquid.

Install in pipelines which are always full

The sensor must always be completely filled with liquid. Therefore avoid:

• Installation at the highest point in the pipe system
• Installation in vertical pipes with free outlet

Do not install in pipelines which can run empty

For partially filled pipes or pipes with downward flow and free outlet the flowmeter should be located in a U?Tube.

Install in U-tubes when pipe is partially filled

Installation in vertical pipes

Recommended flow direction: upwards. This minimizes the effect on the measurement of any gas/air bubbles in the liquid.

Install in vertical pipes with upward flow direction

Installation in horizontal pipes

The sensor must be mounted as shown in the below figure. Do not mount the sensor as shown in the lower figure. This will position the electrodes at the top where there is possibility for air bubbles and at the bottom where there is possibility for mud, sludge, sand etc.

Measuring abrasive liquids and liquids containing particles

Recommended installation is in a vertical/inclined pipe to minimize the wear and deposits in the sensor.

Install in vertical pipelines with upward flow direction if measuring abrasive liquids

Inlet and outlet conditions

Recommended straight pipe lengths up and downstream for installations between elbows, pumps and valves

To achieve maximum accurate flow measurement it is essential to have straight pipe lengths up and downstream. Practical experience has proved that the MAG 5100 W and MAG 8000 are capable to operate in non-optimal piping arrangements and still provide acceptable accuracy even with zero diameters upstream and downstream of straight run pipe.

It is also important to center the flowmeter in relation to pipe flange and gaskets.

Ambient temperature-Installation

Temperature changes can cause expansion or contraction in the pipe system. To avoid damage on the sensor use of proper gasket and torque should be ensured. For more information see sensor instruction.

Potential equalization

Potential equalization

The electrical potential of the liquid must always be equal to the electrical potential of the sensor. This can be achieved in different ways depending on the application:

• Wire jumper between sensor and adjacent flange (MAG 1100, MAG 3100)
• Direct metallic contact between sensor and fittings (MAG 1100 F)
• Built-in grounding electrodes (MAG 3100, MAG 5100 W)
• Optional grounding/protection flanges/rings (MAG 1100, MAG 3100, MAG 8000)
• Optional graphite gaskets on MAG 1100 (standard for MAG 1100 High Temperature)
• MAG 8000 installed in plastic or coated pipes: two grounding rings to be used.

Grounding

MAG 3100 and MAG 5100 W: with grounding electrodes in conductive and non-conductive pipes (no further action necessary)

MAG 1100 and MAG 3100; without grounding electrodes in conductive pipes (MAG 1100 use graphite gasket)

Without grounding electrodes in non-conductive pipes use grounding ring(MAG 1100 use graphite gasket)

MAG 1100 F grounding via process connections. MAG 8000 grounding see MAG 8000 pages.

Vacuum

In order to prevent damages of liner when operating meters under vacuum please take note of the information "Operating pressure" given in section "Technical specification".

Installation in large pipes

Reduction in nominal pipe diameter

The flowmeter can be installed between two reducers (e.g. DIN 28545). Assuming that at 8° the following pressure drop curve applies. The curves are applicable to water.

Pressure drop as function of diameter reduction between reducers

Example:

Flow velocity (v) of 3 m/s (10 ft/s) in a sensor with a diameter reduction DN 100 (4") to DN 80 (3") (d₁/d₂ = 0.8) gives a pressure drop of 2.9 mbar (0.04 psi).

Ambient temperature

Max. ambient temperature as a function of temperature of medium

The transmitter can be installed either compact or remote.

With compact installation the temperature of medium must be according to the graph.

Sensor cables and conductivity of medium

Compact installation:

Liquids with an electrical conductivity ? 5 ?S/cm.

Remote installation

Minimum conductivity of medium (using standard electrode cable)

Minimum conductivity of medium (using special electrode cable)

Empty pipe detection

The installation has to fulfill the following limitations for usage of the empty pipe detection function:

• media conductivity ? 20 ?S/cm
• length of cable at remote installation ? 50 m (150 ft)
• special shield cable must be used

Note for MAG 1100 sizes DN 2 and DN 3:

• empty pipe detection is not available
• the media conductivity must be ? 30 ?S/cm

Note for MAG 5000/6000 CT:

• empty pipe detection is not available