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Maintenance and service guide - LSN-FLSN ZONE
2 - Ex ec
5724 en - 2020.02 / c
INSTALLATION AND MAINTENANCE – LSN-FLSN ZONE 2 – Ex ec
10.6 - IP Leak tightness of motor
WHENEVER removed during preventative
maintenance replace seals (shaft passages,
bearing recesses, terminal box cover etc.) if made of
sealant using new seals with the same characteristics
after cleaning the components. Shaft passage seals
must be fitted using the same type of grease as the
bearings.
After every removal of drain plugs, refit them to
ensure the IP degree of protection plated on the
motor. Replace the seals that are removed using new
seals with the same characteristics. Clean the orifices
and plugs before refitting them.
After removal of the terminal box cover, replace the
seal using a new seal of the same type after
cleaning the components if its condition no longer
guarantees the required degree of protection.
In the case of an "eb or “ec” type connection box:
- In the case of a ‟eb or ec’’ type box, if the threaded hole(s) of
the orifice(s) intended to receive cable gland(s) or conduit(s)
have/has metric threads, there is no specific marking present
on the motor. If the type of thread is different or mixed, the
type(s) are marked on the equipment.
- When closing ‟eb or ec’’ connection boxes, check that all
seals are correctly positioned (bond them onto one of the
components) and that the screws are correctly tightened in
order to guarantee the IP degree of protection that is marked
on the nameplate.
10.7 - Groups IIC (> 200 µm) and group
III paints: electrostatic risk
IEC EN 60079-0 §7.4 reminder:
Preventing electrostatic charge development on an item of
equipment:
Maximum thickness of non-metallic layer (paint):
Group IIB = 2 mm ; Group IIC = 0.2 mm ; Group III = no limit.
The instructions must provide users with recommendations for
reducing the risk of electrostatic discharges to as great an
extent as possible.
Physical effects:
• Paint gives rise to electrostatic risks due to friction: during
cleaning for example.
• Charges suspended in the air may be attracted by the
paint and thus give it an electrostatic charge: charge by
influence.
Nidec Leroy-Somer recommendations:
• Earth continuity between the various metallic parts must
be ensured: frame, bearing housings, fan cover etc.
• The equipment must be permanently connected to earth.
• The motor must be cleaned using a damp cloth or using
means which do not cause friction on the paint: using an
ionised air-gun, for example.
• Users must prevent the paint gaining an electrostatic
charge. For example: by making motor operation
dependent on the level of humidity in the place it is
located or by ionising the surrounding air.
Users must carry out an assessment of the
electrostatic risks in order to meet the requirements of
guide IEC/TS 60079-32-1
