Screening/Potential Matching; Degree Of Protection; Post-Connection Check - Endress+Hauser Levelflex M FMP40 Interface Brief Operating Instructions

Wiring
Overvoltage protection
If the measuring device is used for the level measurement in flammable liquids which requires
the use of an overvoltage protection according to DIN EN 60079-14, standard for testprocedures
DIN IEC 60060-1 (10 kA, Puls 8/20 μs) it has to be ensured that
• the measuring device with integrated overvoltage protection with gas discharge tubes within
the T12-enclosure is used, refer to product overview in the Operating Instructions on CD-ROM
or
• this protection is achieved by the use of other appropriate measures (external protection
devices e.g. HAW262Z).
3.5

Screening/potential matching

• You achieve optimum screening against disturbances if the screening is connected on both
sides (in the cabinet and on the device). If you have to reckon with potential equalisation
currents in the plant, only earth screening on one side, preferably at the transmitter.
• When using in hazardous areas, you must observe the applicable regulations and the separate
Ex documentation.
3.6

Degree of protection

• with closed housing tested according to:
– IP68, NEMA6P (24 h at 1.83 m under water surface)
– IP66, NEMA4X
• with open housing: IP20, NEMA1 (also ingress protection of the display)
3.7

Post-connection check

After wiring the measuring instrument, perform the following checks:
• Is the terminal allocation correct (→ ä 12)?
• Is the cable gland tight?
• Is the housing cover screwed tight?
• If auxiliary power is available: Is the instrument ready for operation and is the liquid crystal
display visible?
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Levelflex M FMP40 4...20 mA HART
Endress+Hauser