92
Selection and protection of a motor
(2) Electronic thermal relay function pre-alarm (TH) and alarm signal (THP signal)
(3) External thermal relay input (OH signal)
The alarm signal (THP) is output and electronic thermal relay function pre-alarm (TH) is displayed when the
electronic thermal O/L relay cumulative value reaches 85% of the level set in Pr. 9. If it reaches 100% of the Pr. 9
Electronic thermal O/L relay setting electronic-thermal relay protection (E.THM) occurs.
The drive unit does not trip even when the alarm signal (THP) is output.
For the terminal used for the THP signal output, assign the function by setting "8 (positive logic) or 108 (negative
logic)" in Pr. 190 or Pr. 192 (output terminal function selection) .
100%: Electronic thermal O/L relay alarm operation value
NOTE
Changing the terminal assignment using Pr. 190, Pr. 192 (output terminal function selection) may affect the other functions.
Set parameters after confirming the function of each terminal.
To protect the motor against overheat, use the OH signal when using an external
thermal relay or the built-in thermal protector of the motor.
When the thermal relay operates, the drive unit trips and outputs the fault signal
(E.OHT).
For the terminal used for OH signal input, assign the function by setting "7" in any of
Pr. 178 to Pr. 182 (input terminal function selection) .
External thermal relay input
connection example
NOTE
Changing the terminal assignment using Pr. 178 to Pr. 182 (input terminal function selection) may affect the other
functions. Set parameters after confirming the function of each terminal.
Electronic thermal
relay function
operation level
Electronic thermal
O/L relay alarm
(THP)
OFF
ON
100%
85%
Time
ON
Drive unit
U
V
W
OH
SD
Thermal relay
protector
Moto
M
