Thermal Protection Of Motor (Electronic Thermal); Electronic Thermal Setting - Omron RX2 Series User Manual

6 Basic Parameter Settings
6-6 Thermal Protection of Motor
(Electronic Thermal)
6-6-1

Electronic Thermal Setting

Electronic thermal setting enables a motor to be protected from thermals.
Change of Electronic Thermal Level
Setting in accordance with the motor rated current protects the motor from continuous current flows. To
make the protection earlier, the protection level should be set lower than the motor rated current.
(Ex.1) Motor rated current 64A ([bC110]=64.0A)
Setting range:12.8A(20%) to 204.0A(300%)
When driven at a base frequency
Trip time (s)
Precautions for Correct Use
• Make the setting correctly as this is necessary to protect the motor.
• When the thermal protection begins, [E005] motor electronic thermal error occurs.
• Irrespective of the thermal setting of the motor, the inverter electronic thermal protection
works independently to protect the inverter.
• When the current grows rapidly, [E001] excessive current error could occur before [E005]
motor electronic thermal error.
• Even electronic thermal level is set high, electronic thermal for the inverter works separately
and it may be reduced from 5 Hz while the reduction ratio may be × 0.8 at 0 Hz.
The electronic thermal time-limited characteristics is shown in (Ex.1) when the electronic thermal level
setting, 1st-motor [bC110] is 64A
Example 1 shows the case of reduction ratio x1. (For example, the case of the motor driven at a base
frequency for [bC111]=01.)
The magnification ratio and hence the time to a trip could change depending on the choice of the elec-
tronic thermal characteristic.
A trip occurs in 60 seconds when an electric current of 150% of the electronic thermal level x1 flows
continuously.
6 - 48
60
3
0
128
70.4 96
(200%)
(110%) (150%)
Output current (A)
(Ratio to motor rated current)
High-function General-purpose Inverter RX2 Series User's Manual