Panasonic M41A1G4L Operating Instructions Manual page 30

Motor selection
Service factor
Life expectancy of motor varies depending on load fluctuation. To determine the life expectancy, a factor called
service factor, as shown in the table below is used.First choose the appropriate service factor according to the
type of load and multiply the result by the required power to determine the design power.
• Service factor
Type of load Typical load
Constant Belt conveyor, One-directional rotation
Light-impact Start/Stop, Cam-drive
Medium-impact Instant FWD/REV, Instant stop
Heavy-impact Frequent medium-impact
• Standard life expectancy
Life (hours)
Ball bearing 10000 hours*
Metal bearing
2000 hours
Right-angle 5000 hours
* 5,000 hours when used on reversible motor
The standard life can be expected when the product is operated at service factor 1.0.
The life of a component during particular application is estimated by dividing the standard life expectancy by the
service factor. If the service factor is 2.0, then the actual life will be one half the expected life.
Overhung load and thrust load
The overhung load is defined as a load applied to the output shaft in the
right-angle direction. This load is generated when the gear head is coupled to
the machine using a chain, belt, etc., but not when the gear head is directly
connected to the coupling. As shown in the right figure, the permissible value
is determined based on the load applied to the L/2 position of the output shaft.
The thrust load is defined as a load applied to the output shaft in the axial
direction. Because the overhung load and thrust load significantly affect the
life of the bearing, take care not to allow the load during operation to exceed
the permissible overhung load and thrust load shown in the table below.
Permissible Permissible
overhung load thrust load
Size Output
(W)
N (kgf) lbf N (kgf)
4P 1 W 39 (4) 8.8 1.5 (0.15)
42 mm sq.
(1.65 inch sq.)
2P 3 W 39 (4) 8.8 1.5 (0.15)
60 mm sq.
4P 3 W to 6 W 49 (5) 11 7 (0.7)
(2.36 inch sq.)
70 mm sq.
Motor 4P 10 W to 15 W 49 (5) 11 7 (0.7)
(2.76 inch sq.)
unit
4P 15 W to 25 W 108 (11) 24 12 (1.2)
80 mm sq.
(round
(3.15 inch sq.)
2P 20 W to 60 W 118 (12) 26 12 (1.2)
shaft)
4P 40 W 157 (16) 35 20 (2)
4P 60 W to 90 W 255 (26) 56 20 (2)
90 mm sq.
(3.54 inch sq.)
2P 60 W 118 (12) 26 20 (2)
2P 90 W to 150 W 147 (15) 33 20 (2)
Panasonic Corporation Electromechanical Control Business Division
industrial.panasonic.com/ac/e/
Service factor
5 hours/day 8 hours/day 24 hours/day
0.8 1.0
1.2 1.5
1.5 2.0
2.5 3.0
Life (hours)
42 mm sq. 2000 hours
Round shaft
10000 hours*
for C&B motor 5000 hours
W (Overhung load)
L L
2 2
F (Thrust load)
L
MX G, MZ9G, MY9G, MR9G, MP9G type
□
Permissible Permissible
overhung load thrust load
Size Model
(F) (W)
lbf N (kgf) lbf N (kgf)
42 mm sq.
0.3 M4GA □ F 20 (2) 4.4 15 (1.5)
(1.65 inch sq.)
0.3 MX6G □ B(A) 98 (10) 22
60 mm sq.
29 (3)
(2.36 inch sq.)
1.5 MX6G M(A) 49 (5) 11
□
1.5 MX7G B(A) 196 (20) 44
□
70 mm sq.
39 (4)
(2.76 inch sq.)
2.6 MX7G □ M(A) 98 (10) 22
2.6 MX8G □ B 294 (30) 66
80 mm sq.
49 (5)
(3.15 inch sq.)
4.4 MX8G M 196 (20) 44
□
4.4 MX9G B 392 (40) 88
□
98 (10)
4.4 MX9G M 294 (30) 66
□
90 mm sq.
(3.54 inch sq.)
4.4 MZ9G □ B
588 (60) 132 147 (15)
MY9G □ B
90 mm sq.
MR9G B
□
(3.54 inch sq.) 784 (80) 176 147 (15)
MP9G B
High torque □
90 mm sq.
MX9G □ R 392 (40) 88 98 (10)
(3.54 inch sq.)
MZ9G □ R 588 (60) 132 147 (15)
Right-angle
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© Panasonic Corporation 2018 AQCTB02E 201806-E
Calculation of motor capacity
1. Speed suitable for use
Fig. 1 shows the typical torque curve, input dissipation curve and
vibration curve.
In Fig. 1, the motor shows variations of 1100 [r/min] to 1800 [r/min]
according to the load. The speed most suitable for the load of the
equipment is as follows:
1200 [r/min] to 1250 [r/min] for 50 Hz
1.5
1500 [r/min] to 1550 [r/min] for 60 Hz
2.0
In this speed range, as can be seen from Fig. 1, the input
2.5
dissipation becomes minimum, which means that the temperature
3.5
rise of the motor is reduced accordingly.
As a result, the life of the motor, the insulation life, ball bearing
grease life, etc. in particular, is prolonged. Also the vibration is
minimized: in particular the gear noise caused when a gear head is
used is reduced optimally. As described above, an optimum speed
should be considered in selecting a motor.
2. Examination of load of equipment
Examine the torque required for the load regarding the following
three items.
• Minimum required torque at starting of the equipment
• Maximum load torque at load variations of the equipment
• Load torque at stable rotation
When the load torque is (1) to (4) in Fig. 2, the starting torque for
(1), the stalling torque for (2) both the starting torque and stalling
torque for (3) and (4) should be considered.
3. Calculation of required torque
• When the load of the equipment is (1), (3) or (4) in Fig. 2
Calculate the approximate value of the required starting torque Ts. In
Fig. 3 (Conveyor), for example, calculate the required force F from
"T = Fr". Then select suitable motors from our catalog or the attached
S-T data and check the minimum starting voltage, the minimum stable
voltage and the speed in stable rotation. In accordance with the
equipment load status calculated based on the above-mentioned
examination, select a motor with the most suitable S-T curve.
(F)
lbf
3.3 4. Measurement of minimum starting voltage
6.6
Couple the motor to the load to be measured and connect a variable
transformer and voltmeter as shown in the figure to the right.
8.8
Increase the voltage continuously from 0 volt at the rate of 3 V/sec
with this variable transformer and measure when the rotating part of
11
the equipment starts and gets ready for acceleration.
22
33
5.Measurement of minimum stable voltage
33
Drive the equipment in a stable state. Using the above-mentioned variable transformer, decrease the voltage
gradually. Measure the voltage at the limit of the motor speed allowing the equipment to function, that is, when
22
the equipment begins to stop.
33
Panasonic Corporation Electromechanical Control Business Division
industrial.panasonic.com/ac/e/
Fig. 1 Example of Various
Characteristics (60 Hz)
Input dissipation curve
Torque curve
Vibration curve
1100 1500 1800
Speed (r/min)
Fig. 2 Type of Load
(1)
0
(Speed) (Rated speed)
Fig. 3. Example of belt Conveyor
r
F
Variable transformer
– A-57 –
© Panasonic Corporation 2018 AQCTB02E 201806-E
(2)
(3)
(4)