Mitsubishi Electric FR-F820-00077 Instruction Manual page 325

Parameters
Electronic thermal O/L relay when using IPM motor (Pr. 9)
● This function detects the overload (overheat) of the motor and trips the inverter by stopping the
operation of the transistor at the inverter output side. (The operation characteristic is shown
below.)
● Set the rated current (A) of the motor in Pr. 9. Performing IPM parameter initialization automati-
cally sets the rated current of the IPM motor. (Refer to page 5-180.)
● Set "0" in Pr. 9 to avoid activating the electronic thermal O/L relay function; for example, when
using an external thermal relay for the motor.
(Note that the output transistor protection of the inverter is activated. (E.THT))
Fig. 5-46:
The % value denotes the percentage to the rated motor current.
● Protective function activated area: the area right of the characteristic curve
● Normal operation area: the area left of the characteristic curve
NOTES The internal accumulated heat value of the electronic thermal relay function is reset to the initial
value by the inverter's power reset and reset signal input. Avoid unnecessary reset and power-
OFF.
When using a PM motor other than MM-EFS/MM-THE4, set the free thermal parameters (Pr. 600 to
Pr. 604) in accordance with the motor characteristic.
The transistor protection thermal O/L relay is activated early when the Pr. 72 "PWM frequency
selection" is increased.
FR-F800
MM-EFS (1500 r/min specification), MM-THE4
70
150 r/min
500 r/min
60
50
240
150 r/min
180
500 r/min
120
60
0
0 20 40 60 80 100 120 140 160 180 200
Inverter output current [%]
Electronic thermal relay function operation characteristic (MM-EFS, MM-THE4)
750 r/min
1125 r/min
1500 r/min
750 r/min
1125 r/min
1500 r/min
(H) Protective function parameter
MM-EFS (3000 r/min specification)
70
1500 r/min
300 r/min
2250 r/min
1000 r/min
60
3000 r/min
50
240
300 r/min
180
1000 r/min
120
60
0
0 20 40 60 80 100 120 140 160 180 200
Inverter output current [%]
1500 r/min
2250 r/min
3000 r/min
I003019E_B
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