Proline Promass O 300
Hauser
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System pressure
It is important that cavitation does not occur, or that gases entrained in the liquids do not outgas.
This is prevented by means of a sufficiently high system pressure.
For this reason, the following mounting locations are recommended:
• At the lowest point in a vertical pipe
• Downstream from pumps (no danger of vacuum)
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Thermal insulation
In the case of some fluids, it is important to keep the heat radiated from the sensor to the
transmitter to a low level. A wide range of materials can be used for the required insulation.
The following device versions are recommended for versions with thermal insulation:
Version with extended neck:
Order code for "Measuring tube material", option FA with an extended neck length of
105 mm (4.13 in).
NOTICE
Electronics overheating on account of thermal insulation!
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Recommended orientation: horizontal orientation, transmitter housing pointing downwards.
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Do not insulate the transmitter housing .
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Maximum permissible temperature at the lower end of the transmitter housing: 80 °C (176 °F)
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Thermal insulation with extended neck free: We recommend that you do not insulate the
extended neck in order to ensure optimum dissipation of heat.
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Thermal insulation with extended neck free
Heating
Some fluids require suitable measures to avoid loss of heat at the sensor.
Heating options
• Electrical heating, e.g. with electric band heaters
• Via pipes carrying hot water or steam
• Via heating jackets
NOTICE
Danger of overheating when heating
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Ensure that the temperature at the lower end of the transmitter housing does not exceed
80 °C (176 °F).
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Ensure that sufficient convection takes place at the transmitter neck.
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Ensure that a sufficiently large area of the transmitted neck remains exposed. The uncovered
part serves as a radiator and protects the electronics from overheating and excessive cooling.
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If using in potentially explosive atmospheres, observe the information in the device-specific Ex
documentation. For detailed information on the temperature tables, see the separate document
entitled "Safety Instructions" (XA) for the device.
Vibrations
The high oscillation frequency of the measuring tubes ensures that the correct operation of the
measuring system is not influenced by plant vibrations.
Summary of Contents for Proline Promass O 300
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