Endress+Hauser Proline Promass 80E, Техническая информация

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Proline Promass 80E, 83E
Hauser 23
System pressure It is important to ensure that cavitation does not occur, because it would influence the oscillation of the
measuring tube. No special measures need to be taken for fluids which have properties similar to water
under normal conditions.
In the case of liquids with a low boiling point (hydrocarbons, solvents, liquefied gases) or in suction
lines, it is important to ensure that pressure does not drop below the vapor pressure and that the liquid
does not start to boil. It is also important to ensure that the gases that occur naturally in many liquids
do not outgas. Such effects can be prevented when system pressure is sufficiently high.
Therefore, the following locations should be preferred for installation:
• Downstream from pumps (no danger of vacuum)
• At the lowest point in a vertical pipe
Thermal insulation Some fluids require suitable measures to avoid loss of heat at the sensor. A wide range of materials can
be used to provide the required thermal insulation.
Heating Some fluids require suitable measures to avoid heat transfer at the sensor. Heating can be electric, e.g.
with heated elements, or by means of hot water or steam pipes made of copper or heating jackets.
"
Caution!
• Risk of electronics overheating! Make sure that the maximum permissible ambient temperature for
the transmitter is not exceeded. Consequently, make sure that the adapter between the sensor and
transmitter and the connection housing of the remote version always remain free of insulating
material. Note that a certain orientation might be required, depending on the fluid temperature
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19.
• If using an electric trace heating system whose heating is regulated via phase angle control or pulse
packages, influence on the measured values cannot be ruled out due to magnetic fields (i.e. for values
that are greater than the values approved by the EN standard (sine 30 A/m)). In such cases, the
sensor must be magnetically shielded.
The housing can be shielded with tin plates or electric sheets without preferential direction
(e.g. V330-35A) with the following properties:
– Relative magnetic permeability μ
r

300
– Plate thickness d  0.35 mm (d  0.014")
• Information on permitted temperature ranges
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Special heating jackets, which can be ordered separately from Hauser as an accessory, are
available for the sensors.