What is 'CoolBLUE® Inductive Absorber'?

In the given configuration CoolBLUE® soft magnetic cores work as a single turn common mode suppression choke. They do not affect the symmetrical power currents but efficiently dampen the asymmetrical radio frequency noise currents. CoolBLUE® also suppresses the asymmetrical EMI currents which are generated by the parasitic currents of the motor itself together with the motor cable.

CoolBLUE® Nanocrystalline absorbers are superior to other soft magnetic materials like ferrites because of significant advantages concerning their magnetic properties. As a consequence only about 20% of ‘magnetic mass’ is required – i.e. a significantly reduced number of cores is suitable.


No maintenance required on the cores. Once installed, they last a lifetime, and can even be left on the system if a new motor or drive is installed.

Why install the CoolBLUE® cores close to the drive, instead of on the shaft where the discharge is occurring?

Very simply, CoolBLUE® cores ‘absorb’ the energy caused by the VFD’s at the source…before getting to the motor.

Section 4