Mitsubishi Electric FR-D720S SC EC Instruction Manual page 219

Parameter
Set two different electronic thermal O/L relays (Pr. 51)
Use this function when running two motors of different rated currents individually by a single in-
verter. (When running two motors together, use external thermal relays.)
Set the rated current of the second motor to Pr. 51. When the RT signal is on, thermal protection
is provided based on the Pr. 51 setting.
For the terminal used for RT signal input, set "3" in any of Pr. 178 to Pr. 182 to assign the function.
Pr. 450
Second applied
motor
9999
9999
≠ 9999
≠ 9999
Tab. 6-5: Switching the electronic thermal O/L relay
¼
Output current value is used to perform integration processing.
Output current is assumed as 0A to perform integration processing. (cooling processing)
— Electronic thermal relay function is not activated.
NOTE
The RT signal acts as the second function selection signal and makes the other second
functions valid. (Refer to section 6.9.3.)
FR-D700 SC EC
M
3~
M
3~
Pr. 9
Electronic thermal Second electronic
O/L relay thermal O/L relay
0
≠ 0
0
≠ 0
0.01–500 (0.1–3600)
Selection and protection of a motor
Fig. 6-34:
Running two motors by a single inverter
Pr. 51 RT = OFF
1. Motor 2. Motor 1. Motor 2. Motor
9999 —
0 —
0.01–500 —
¼
9999
¼
0
¼
0.01–500
9999 —
0 —
0.01–500 —
¼
9999
¼
0
¼
I001137C
RT = ON
— — —
— — —
¼
—
¼
— —
— —
¼
— — —
— — —
¼
—
¼
— —
¼
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