*
For additional assistance, please contact Toshiba Adjustable Speed Drive Marketing Dept. at (800) 872-
2192
73
The following software limit curve applies to all G3’s 125HP and larger:
For specific de-rates go to the
CF Derate Calculator.
Carrier Frequency Derate 125HP and Larger
0
0.2
0.4
0.6
0.8
1
1.2
0
1
2
3
4
5
6
7
8
9
10
11
12
Carrier Frequency
Derate Multiplier
High carrier frequencies (in the range of 10 – 12KHz) have the benefit of shifting a motor’s audible noise
to a frequency that is not heard by the human ear. It can also have some benefits in reduced output filter
costs. The downsides include, increased thermal stress on the transistors or a required drive derate,
increased stress on motor insulation and increased opportunity for common mode bearing current
problems.
Prior to increasing carrier frequencies on a drive, it is best to consult with the factory to make sure that the
proper decision is being made.
