Mitsubishi Electric FR-A820-00046 Instruction Manual page 478

(H) Protective function parameter
External thermal relay input (OH signal, E.OHT)
External thermal relay input connection diagram
● The external thermal relay input (OH) signal is used when using an external thermal relay or a
thermal protector built into the motor to protect the motor from overheating.
● When the thermal relay function is activated, the external thermal operation (E.OHT) shuts off the
inverter output.
● For the terminal used for the OH signal input, set "7" in any of Pr. 178 to Pr. 189 (input terminal
function selection) to assign the function.
● Vector-control-dedicated motors (SF-V5RU) are equipped with thermal protectors.
Fig. 5-127:
Connect the recommended 2 W 1 kΩ resistor between the terminal PC and OH. (Refer to page 2-67.)
● When the control terminal option (FR-A8TP) is used, valid/invalid setting of the terminal OH can
be changed using Pr. 876 "Thermal protector input".
NOTE Changing the terminal assignment using Pr. 178 to Pr. 189 (input terminal function selection) may
affect the other functions. Set parameters after confirming the function of each terminal.
5 - 298
Thermal relay protector
Inverter
Motor
U
V
M
W
OH
SD
Inverter
Connecting the SF-V5RU thermal protector
Fig. 5-126:
Connection of an external thermal relay
SF-V5RU
PC
2 W 1 kΩ
G1
OH
G2
SD
Parameters
I002582E
I002583E