Mitsubishi Electric FR-A820-00046 Instruction Manual page 476

(H) Protective function parameter
Set two types of electronic thermal O/L relays (Pr. 51)
● These settings are used when rotating two motors with different rated current separately by a
single inverter. (When rotating two motors together, use an external thermal relay.)
● Set the rated motor current for the second motor in Pr. 51.
● When the RT signal is ON, thermal protection is provided based on the Pr. 51 setting.
"Second applied
Other than 9999
Other than 9999
: Values are accumulated by using the output current.
Δ : Values are accumulated by assuming the output current is "0 A" (cooling processing).
× : Electronic thermal O/L relay does not operate.
Tab. 5-117: Switching of the electronic thermal relay
NOTES The RT signal is a second function selection signal. The RT signal also enables other second func-
tions. (Refer to page 5-428.)
The RT signal is assigned to the terminal RT in the initial setting. Set "3" in any of Pr. 178 to Pr. 189
(input terminal function selection), to assign the RT signal to another terminal.
5 - 296
MC
MC
U
V
W
RT
SD
Pr. 450 Pr. 9
"Electronic thermal
motor" O/L relay"
9999 0
9999 Other than 0
0
Other than 0
Fig. 5-123:
Operating two motors by a single inverter
IM
IM
Pr. 51
"Second electronic
thermal O/L relay"
9999
0
0.01 to 500 (0.1 to 3600)
9999
0
0.01 to 500 (0.1 to 3600)
9999
0
0.01 to 500 (0.1 to 3600)
9999
0
0.01 to 500 (0.1 to 3600)
Parameters
RT-OFF RT-ON
No.1 No.2 No.1
Motor Motor motor
× × ×
× × ×
× Δ ×
 
×

× Δ

Δ Δ
× × ×
× × ×
× Δ ×

Δ Δ

× Δ

Δ Δ
I002581E
No.2
motor
×
×

×
×

×
×


×
