Motor Protection; Motor Overload Detection - Omron VARISPEED V7 User Manual

Motor Protection

Motor Overload Detection

The V7AZ protects against motor overload with a built-in electronic
thermal overload relay.
Motor Rated Current (Electronic Thermal Reference Current,
n036)
Set the rated current value shown on the motor nameplate.
Note: Setting n036 to 0.0 A disables the motor overload protective function.
Motor Overload Protection Selection (n037, n038)
n037
Setting
0
1
2
Constant
No.
n038
The electronic thermal overload function monitors the motor tempera-
ture based on Inverter output current and time to protect the motor from
overheating. When the electronic thermal overload relay is enabled, an
error occurs, and the Inverter output is turned OFF to prevent
excessive overheating in the motor. When operating with one Inverter
connected to one motor, an external thermal relay is not needed. When
operating more than one motor with one Inverter, install a thermal relay
on each motor.
General-purpose Motors and Inverter Motors
Induction motors are classified as general-purpose motors or Inverter
motors based on their cooling capabilities. The motor overload function
operates differently for these two motor types.
136
Electronic Thermal Characteristics
For general-purpose motor
For Inverter motor
Electronic thermal overload protection not provided.
Name
Electronic Thermal
Motor Protection
Time Constant Set-
ting
Unit Setting Range
1 min 1 to 60 min
Factory
Setting
8 min