Mitsubishi Electric FR-A700 Series, Technical Manual

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SELECTION
3.3.10 Synchronous motor
Synchronous motor is not available in general.
Synchronous motor may not synchronize to inverter output
frequency, and may not start. And even if the motor is started, depending on a load, difference in synchronization
may occur.
3.3.11 Single phase motor
It is not recommended to use a single-phase motor with an
inverter. The small capacity of the single-phase motor is
often rated at 100V and does not match the inverter. The
SC, SL, SCL and other motors with capacitors cause an
excessive current to flow in the capacitor, resulting in
capacitor breakage. A split-phase-start or repulsion-start motor cannot be used
because this will cause the centrifugal switch to be
deactivated. (The starting winding will be burned out in a
short time.)
3.3.12 Permissible maximum frequency of general-purpose motor
(1) Standard models
Drip-proof protection motor: SB-JR(F, V)
Totally-enclosed fan-cooled motor:
SF-JR(F, V)
*1 The value in the parentheses indicates synchronous
speed.
*2 When a two-pole motor of frame number 90 or 100 is run
at 120Hz, noise will exceed 90dB (A).
(2) Other models
3.3.13 Inverter-driven 400V motor
In the PWM type inverter, a surge voltage attributable to
wiring constants is generated at the motor terminals.
Especially for a 400V class motor, the surge voltage may
deteriorate the insulation. When the 400V class motor is
driven by the inverter, consider the following measures:
z Countermeasure
It is recommended to take either of the following measures:
(1) Reinforcing the motor insulation and
limiting the PWM carrier frequency
according to the wiring length
For a 400V class motor, use an insulation-enhanced
motor. Specifically:
1) Specify the "400V class inverter-driven, insulation-
enhanced motor".
2) As a dedicated motor such as a constant-torque
motor or low-vibration motor, use a "motor
dedicated to inverter operation".
3) Set [ Pr. 72 PWM frequency selection ] as indicated
below according to the wiring length.
(2) How to suppress surge voltage on the
inverter side
Connect the surge voltage suppression filter (FR-
ASF-H or FR-BMF-H) to the 55K or less and the sine
wave filter (MT-BSL/BSC) to the 75K or more on the
inverter output side.
2 4 6
63
120Hz (*2)
(7200 r/min) 120Hz
(3600 r/min)
120Hz
(2400 r/min)
71
80
90
100
112 90Hz
(5400 r/min) 132
160
75Hz
(4500 r/min) 100Hz
(3000 r/min)
180
65Hz
(3900 r/min)
200 60Hz
(3600 r/min)
65Hz
(1950 r/min)
65Hz
(1300 r/min) 225
Number
of poles
Frame
Number
2 4 6
With TB brake
Not
available
65Hz
(except
vertical
type)
90Hz
(except
vertical
type)
Outdoor
type
Waterproof
type
63 to 132
65Hz
120Hz
120Hz
160 100Hz
180
65Hz
90Hz
200
60Hz 65Hz
225
Number of
poles
Models/
Frame Number
Wiring Length
50m or less 50m to 100m
More than
100m
[ Pr. 72 PWM
frequency
selection
]
15(14.5kHz)
or less
9(9kHz) or less
8(8kHz) or less
4(4kHz) or less
2(2kHz) or less
A700 F700
E700 D700
A700 F700
E700 D700