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6 Basic Parameter Settings
High-function General-purpose Inverter RX2 Series User’s Manual
6-6 Thermal Protection of Motor (Electronic Thermal)
6
6-6-1 Electronic Thermal Setting
Constant Torque Characteristics [bC111]=01
Use this setting to use the constant-torque motor
(Ex.3) For induction motor rated current: 64A, [bC110]=64(A)
Base frequency [Hb104]=50 Hz, output frequency =5 Hz
When the first electronic thermal level [bC110] is 64 A, the reduction ratio is ×1.0 for operations at a
base frequency of 50 Hz and output frequency of 5 Hz and the electronic thermal time-limited char-
acteristics are given in the lower part of Example 3.
Since Example 1 shows the case of the reduction ratio ×1, a trip occurs in 60 seconds when an elec-
tric current of 150% ×1 of the motor rated current flows continuously. The performance in the exam-
ple 3 is the same as the one in the example 1.
Free Settings [bC111]=02
To protect the motor, the electronic thermal characteristics can be freely set in accordance with the
load.
Inverter
Output frequency (Hz)
Base frequency
Reduction ratio
70.4
(110%)
96
(150%)
128
(200%)
60
3
0
×1
Trip time (s)
Motor current (A)
(Ratio to motor rated current)