KROHNE H250 M40 EN - Manual (Page 54)

7
SERVICE
54
H250 M40
www.krohne.com 11/2012 - 4000640702 MA H250 M40 R02 en
Service
7.1 Maintenance
Within the scope of routine maintenance of the system and pipelines, the flowmeter should also
be inspected for signs of fouling, corrosion, mechanical wear and leaks, as well as damage to
the measuring tube and indicator.
We advise that inspections be carried out at least once per year.
The device must be removed from the piping before cleaning.
7.2 Replacement and retrofitting
Some of the variable area flowmeter components can be retrofitted:
• Float damping
Indicator M40: Indicator M40: Indicator M40: Indicator M40:
• Limit switch module
• Current output 4-20 mA
• Counter module with LCD and I/O
• Fieldbus interface
7.2.1 Replacing floats
• Remove the device from the piping.
• Take the upper snap ring out of the measuring unit.
• Take the upper float stop and float out of the measuring unit.
• Insert the new float into the centre hole of the lower float stop and push into the measuring
unit along with the upper float catcher. While doing this, the float's upper guide rod must be
guided through the middle hole of the float stop.
• Insert the snap ring into the measuring unit.
• Fit the device back into the piping.
CAUTION!
Pressurized pipes must be depressurized before removing the device.
Empty pipes as completely as possible.
In the case of devices used for measuring aggressive or hazardous media, appropriate safety
precautions must be taken with regard to residual liquids in the measuring unit.
Always use new gaskets when reinstalling the device in the pipeline.
Avoid electrostatic charges when cleaning the surfaces (e.g. sight window)!
CAUTION!
An additional measuring error is to be expected if recalibration is not conducted.
MA_H250_M40_R02_en_640702_PRT.book Page 54 Wednesday, November 28, 2012 12:23 PM