Owner manual

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MOTOR OPERATION AND MAINTENANCE
Maintenance Instructions
The following maintenance instructions apply to all SGA
motors except for hazardous location motors. For
SGAE, SGAN and SGAD motors maintenance must
be carried out by an authorized service agent. Contact
CMG for detailed instructions.
To obtain maximum service life from your electric
motor, it is recommended the following maintenance be
implemented and recorded in a plant log book.
A. Ensure air intake space is unobstructed.
B. On a weekly basis use an air hose to ensure all
airways are clear and free of dust.
C. Do not wash the motor down unless it is IP66 rated.
D. On a quarterly basis:-
i) Check motor terminals for tightness and contact.
ii) If terminal lug/lugs are discolored, re-terminate.
iii) Check operation of starting equipment, ensuring
all terminations are tight.
iv) Check mechanical operation of thermal
overload.
v) Check mechanical operation of thermistor relay
(if tted).
vi) Check operation of space heaters (if tted).
E. On a six (6) monthly basis, in addition to the items in
‘D’ :-
i) Check stator resistance (compare to original and
enter in log book)
ii) Check supply voltage at motor terminals.
iii) Check bearings for noise/overheating.
F. On an annual basis, in addition to the items in ‘D’
and ‘E’ :-
i) Re-grease bearings in line with chart below.
Note: As indicated in the chart, some bearings
may require more frequent grease replacement.
ii) Strip motor down and clean thoroughly.
iii) Check bearings for wear/damage - replace as
necessary.
iv) Check all machine bolts for cracks or damage
- replace as necessary.
v) Check all holding bolts for signs of fatigue/
damage - replace as necessary.
vi) After re-assembly, check and record:-
Full Load Current
Full Load Voltages
Full Load Speed
vii) Ensure cooling fan is operational.
G. Ensure plant log book records commissioning data
and compare maintenance data with original.
Sealed Bearings
The required replacement interval for sealed bearings
is generally determined by the grease life which is
dependant on operating temperature, operating speed,
the limiting speed of the bearing and the type of grease.
Under normal operating conditions the following
relationship applies:-
n n
log t = 6.54 – 2.6
N
– (0.025 – 0.012
N )
T
Where:
t = Average grease life (hours)
n = Speed (RPM)
N = Bearing limiting speed with grease lubrication (RPM)
T = Operating temperature (°C)
For further information, please contact your nearest
CMG ofce for advice.
Open (Regreasable) Bearings
Recommended Grease Replenishment Intervals (Hours)
1)
Bearing Qty of 3000 r/min 1500 r/min 1000 r/min 750 r/min
Bearing bore grease
number [mm] [g] Ball Roller Ball Roller Ball Roller Ball Roller
6312/NU312 60 20 3800 1900 10100 5050 16000 8000 20000 10800
6313/NU313 65 25 3400 1700 9400 4700 15100 7500 20000 10300
6314/NU314 70 30 3000 1500 8800 4400 14300 7150 19500 9750
6315/NU315 75 30 2570 1285 8200 4100 13500 6750 18500 9250
6316/NU316 80 35 2200 1100 7600 3800 12800 6400 17700 8850
6317/NU317 85 40 1800 900 7100 3550 12100 6050 16800 8400
6318/NU318 90 45 1650 825 6600 3300 11500 5750 16000 8000
6319/NU319 95 45 1500 750 5700 2850 9000 4500 14600 7300
6322/NU322 110 60 1200 600 4800 2400 8300 4150 13400 6700
1)
Based on maximum grease service life of 20,000 hours.
It should be noted that for motors tted with Ball and Roller bearings, the lubrication intervals for both bearings should be
based on the roller bearing data.
The re-lubrication intervals recommended are calculated on the basis of normal working conditions.
Note: Air operated grease guns should not be used.
Replenishment of grease media should be by means of a hand held grease gun whilst motor is running with relief plate
removed.
Recommended Lubricant
Use Lithium based grease such as Shell Alvania R3 unless otherwise specied. SGAH, SGASS and SGAHS require
extra high temperature grease, Magnalube G or equivalent.