KROHNE CORIMASS E P MFM 2081 EEx EN - Manual (Page 6)

6 Additional Instruction for Ex version MFM 2081 / 3081
Further requirements / differences are listed below:
• ?The ideal installation factor of an EEx unit is much higher than of a standard system due
to Zener barriers and clamping diodes the EEx system consumes more power during
running. The high installation factor does not mean a lower accuracy.
•
The installation factor should have a value as indicated in the following table.
Meter Size Installation factor
MFM 2081 K/F
MFM 2081 K/F Ex
MFM 3081 K/F
MFM 3081 K/F Ex
< 50
< 100
< 20
< 60
The correct operation of the Zener barriers inside the converter are only guaranteed with a
robust and safe connection of the converter housing with potential earth (potential
compensation PA). Please use the outer earthing connector at the square flange of the
converter housing for earthing.
In case the converter housing has a pressure tight termination compartment, make sure the
connected cable glands / adapters have an Ex certification.
2 Electrical installation
2.1 Location and connecting cables
Location
Do not expose the compact flow meter to direct sunlight. Install a sunshade if necessary.
Connecting cables
To conform to protection category requirements, observe the following recommendations:
• Fit blanking plug PG 16 and apply sealant to unused cable entries.
• In case if the terminal area is EEd, please use approved blanking plug.
•
Do not kink cables directly at cable entries.
•
Provide water drip point (U bend in cable).
•
Do not connect rigid conduit to cable entries.
•
If cables are a tight fit, enlarge inside diameter of cable gland by removing the
appropriate ring(s) from the seal.
2.2 Electrical Connection on converter without intrinsically safe
outputs
Please ensure that the information about power given on the dataplate corresponds to the
locally available mains voltage.
•
Note information given on the instrument dataplate (voltage, frequency)!
•
Electrical connection in conformity with IEC 364 or equivalent national standard.
•
Special regulations apply to installation in hazardous areas. Please refer to separate
"Ex" installation instructions.