Mitsubishi Electric FR-E700 Instruction Manual page 39

∗ Select a UL and cUL certified fuse with Class T fuse equivalent cut-off speed or faster with the appropriate rating for
branch circuit protection, or a UL489 molded case circuit breaker (MCCB) in accordance with the table below.
FR-E720-
Rated fuse voltage(V)
Without power factor
Fuse Maximum
improving reactor
allowable rating
With power factor
(A)∗
improving reactor
Molded case circuit breaker (MCCB)
Maximum allowable rating (A)*
FR-E740-
Rated fuse voltage(V)
Without power factor
Fuse Maximum
improving reactor
allowable rating
With power factor
(A)∗
improving reactor
Molded case circuit breaker (MCCB)
Maximum allowable rating (A)*
∗ Maximum allowable rating by US National Electrical Code. Exact size must be chosen for each installation.
∗ When using the electronic thermal relay function as motor overload protection, set the rated motor current to Pr. 9
Electronic thermal O/L relay.
Electronic thermal relay function operation characteristic
Pr. 9 = 50% setting of inverter rating*1, 2
70
30Hz
or more
*3
20Hz
60
10Hz
6Hz
0.5Hz
50
240
180
120
60
105%
52.5%
50
Inverter output current(%)
(% to the rated inverter current)
Note
⋅ Protective function by electronic thermal relay function is reset by inverter power reset and reset signal input. Avoid
unnecessary reset and power-OFF.
⋅ When multiple motors are operated by a single inverter, protection cannot be provided by the electronic thermal relay
function. Install an external thermal relay to each motor.
⋅ When the difference between the inverter and motor capacities is large and the setting is small, the protective
characteristics of the electronic thermal relay function will be deteriorated. In this case, use an external thermal relay.
⋅ A special motor cannot be protected by the electronic thermal relay function. Use the external thermal relay.
⋅ Electronic thermal relay may not function when 5% or less of inverter rated current is set to electronic thermal relay
setting.
∗ Short circuit current ratings
200V class
Suitable For Use in A Circuit Capable of Delivering Not More Than 5 kA rms Symmetrical Amperes, 264 V Maximum.
400V class
Suitable For Use in A Circuit Capable of Delivering Not More Than 5 kA rms Symmetrical Amperes, 528 V Maximum.
36
KNF 0.1 0.2
15 15
15 15
15 15
KNF 0.4 0.75
6 10
6 10
15 15
Pr. 9 = 100% setting of inverter rating*2
30Hz or more
*3
20Hz
Operation range
10Hz
Range on the right of characteristic curve
6Hz Non-operation range
Range on the left of characteristic curve
0.5Hz
Characteristic when electronic thermal
relay function for motor protection is turned off
(when Pr. 9 setting is 0(A))
Range for
transistor
protection
100
150 230
0.4 0.75 1.5 2.2 3.7
240V or more
15 20 30 40 60
15 20 20 30 50
15 15 20 25 40
1.5 2.2 3.7 5.5 7.5
480V or more
15 20 30 40 70
10 15 25 35 60
15 15 20 30 40
This function detects the overload (overheat)
of the motor, stops the operation of the
inverter's output transistor, and stops the
output.
(The operation characteristic is shown on the
left)
∗1
∗2
∗3
5.5 7.5 11 15
70 80 150 175
60 70 125 150
60 80 110 150
11 15
80 90
70 90
50 70
When using the Mitsubishi constant-torque
motor
1) Set "1" or any of "13" to "16", "50", "53", "54"
in Pr. 71. (This provides a 100% continuous
torque characteristic in the low-speed range.)
2) Set the rated current of the motor in Pr. 9.
When 50% of the inverter rated output current
(current value) is set in Pr. 9
The % value denotes the percentage to the
inverter rated output current. It is not the
percentage to the motor rated current.
When you set the electronic thermal relay
function dedicated to the Mitsubishi constant-
torque motor, this characteristic curve applies
to operation at 6Hz or higher.