WEG M line Series, Инструкция по установке, эксплуатации и обслуживанию

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Installation, operation and maintenance manual – Squirrel cage motor – M line – Vertical 11371757
7.3.5 Insulation Resistance
The insulation resistance must be measured after the
completion of all of the maintenance procedures.
ATTENTION
Before putting the motor back into
operation, it is essential to measure the
winding insulation resistance and ensure
that the measured values meet the
specifications.
7.4 COOLING SYSTEM
MAINTENANCE
In motors with air-air heat exchanger (IC611), the
cooling pipes and noise attenuator (if any) must kept
clean and unobstructed to ensure a perfect heat
exchange. In order to remove the dirt accumulated in
the pipes, a rod with a round brush at the end may be
used. Noise attenuators (if any) can be cleaned with dry
compressed air.
ATTENTION
It is recommended to close the openings of
the external air circuit, if the motor is out of
operation for long terms.
In case of air-water heat exchangers (IC81W), periodic
cleaning in the radiator pipes is necessary to remove all
and any incrustation, according item 7.5.
In open motors (IC01), the air filters should be cleaned
with dry compressed air. If dust is difficult to remove,
wash the filter with cold water and neutral detergent
and dry it in horizontal position. Replace the filters, if
necessary.
7.5 RADIATOR MAINTENANCE
The degree of dirt in the radiator can be detected by the
increase of the temperature at the air outlet. When the
temperature of the cold air, under the same operating
conditions, exceeds the specified value, it can be
assumed that the pipes are dirty.
If corrosion is found in the radiator, it is necessary to
provide adequate protection against corrosion (i.e., zinc
anodes, cover with plastic, epoxy or other similar
products), in order to prevent further damage to the parts
already affected.
The external surface of all the radiator parts must always
be kept in good conditions.
Instructions for removal and maintenance of the
radiator
In order to remove the radiator for maintenance, use the
following procedure:
1.
Close all the water inlet and outlet valves after stopping
the ventilation;
2. Drain the water through the radiator drain plugs;
3. Remove the heads, keeping the bolts, nuts, washers
and seals (gaskets) in a safe place;
4. Brush the inside of the pipes carefully with nylon
brushes in order to remove residues. If damages to the
radiator tubes are found during the cleaning, they must
be repaired;
5. Reassemble the heads, replacing the gaskets, if
necessary.
Sacrificial anodes
Sacrificial anodes are used in radiators that operate with
seawater. The regular inspection must be carried out,
according to the maintenance plan. If excessive corrosion
is found in the sacrificial anode, the frequency of
inspection must be increased in order to determine the
corrosion period and establish a plan for proper
replacement intervals.
7.6 VIBRATION
Any evidence of increase in the unbalance or vibration of
the motor must be investigated immediately.
7.7 ANTI-REVERSION RATCHET
MAINTENANCE
The ratchet anti-reversion condition (if any) must be
inspected according to the maintenance plan described in
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Remove the motor top cover and check the wear of the
pins and gear teeth of the ratchet. If excessive wear is
detected, these parts must be replaced.
7.8 SHAFT GROUNDING DEVICE
The shaft grounding brush (if any) avoids the circulation of
electric current through the bearings, which is detrimental
to their operation. The brush is put in contact with the
shaft and connected by a cable to the motor frame, which
must be grounded. Make sure that the brush holder
fastening and its connection to the frame have been made
correctly.
Figure 7.1: Shaft grounding brush
Drying oil is used to protect the motor shaft against rust
during transportation. In order to ensure the proper
operation of the grounding brush, this oil, as well as any
residue between the shaft and the brush, must be
removed before starting the motor. The brush must be
constantly monitored during operation, and it must be
replaced by another one of the same quality (granulation)
at the end of its useful life.
Shaft