Installation Instructions

Micropilot FMR20 Modbus RS485
18 Endress+Hauser
A0031277
 16 Protective hood, e.g. with 40 mm (1.5") antenna
The sensor is not completely covered by the protective hood.
Free-field measurement with flooding protection tube
The flooding protection tube ensures the sensor measures the maximum level even if it is completely
flooded.
In free-field installations and/or in applications where there is a risk of flooding, the flooding
protection tube must be used.
The flooding protection tube can be ordered as an accessory or together with the device via the
product structure "Accessory enclosed".
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A0031093
 17 Function of flooding protection tube
1 Air pocket
2 O-ring (EPDM) seal
3 Blocking distance
4 Max. level
The tube is screwed directly onto the sensor and seals off the system by means of an O-ring making
it air-tight. In the event of flooding, the air pocket that formed in the tube ensures the measurement
of the maximum level at the end of the tube. Due to the fact that the Blocking distance is inside the
tube, multiple echoes are not analyzed.