Mitsubishi Electric FR-D720S-008SC, Original Instruction

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APPENDIX
Environment
Wiring protection
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 tables below.
* Maximum allowable rating by US National Electrical Code. Exact size must be chosen for each installation.
Motor Overload Protection
The frequency inverters FR-D700 SC are equipped with a UL certified internal electronic thermal relay function.
When using the electronic thermal relay as motor overload protection, set the rated motor current to Pr. 9
Electronic thermal O/L relay .
Electronic thermal relay function operation characteristic
This function detects the overload (overheat) of the motor,
stops the operation of the inverter's output transistor, and
stops the output.
When using the Mitsubishi Electric constant-torque motor
set "1" or any of "13", "50" or "53" in Pr. 71. This provides
a 100 % continuous torque characteristic in the low-speed
range. Set the rated current of the motor in Pr. 9.
*1
When 50 % of the inverter rated output current (current value)
is set in Pr. 9.
*2
The % value denotes the percentage to the inverter rated output
current. It is not the percentage to the motor rated current.
*3
When you set the electronic thermal relay function dedicated
to the Mitsubishi Electric constant-torque motor, this characteristic
curve applies to operation at 6 Hz or higher.
During Operation In Storage During Transportation
Ambient temperature –10 °C to +50 °C –20 °C to +65 °C –20 °C to +65 °C
Ambient humidity
90 % RH or less
(non condensing)
90 % RH or less
(non condensing)
90 % RH or less
(non condensing)
Maximum altitude 1000 m 1000 m 10000 m
FR-D720S-
†††
SC-EC (C) 008 014 025 042 070 100
Rated fuse voltage [V] 240 V or more
Fuse maximum
allowable rating [A] *
Without power factor
improving reactor
15 20 20 30 40 60
With power factor
improving reactor
15 20 20 20 30 50
Molded case circuit breaker (MCCB)
Maximum allowable rating [A] *
15 15 15 20 25 40
FR-D740-
†††
SC-EC (C) 012 022 036 050 080 120 160
Rated fuse voltage [V] 480 V or more
Fuse maximum
allowable rating [A] *
Without power factor
improving reactor
6 10 15 20 30 40 70
With power factor
improving reactor
6 10 10 15 25 35 60
Molded case circuit breaker (MCCB)
Maximum allowable rating [A] *
15 15 15 15 20 30 40
앫
Operation region
Region on the right of
characteristic curve
앫
Non-operation region
Region on the left of
characteristic curve
Characteristic when electronic
thermal relay function for motor
protection is turned OFF
(Pr. 9 = 0 (A))
Region for
transistor
protection
Inverter output current (%)
(% to the rated inverter current)
Pr. 9 = 100 % setting of
inverter rating
*2
Pr. 9 = 50 % setting of
inverter rating
*1, 2
or more
*3
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