common mode current

University Flood and VFD Protection

Recently, a larger University in Indiana suffered a flood in the Main Campus Library. During a large rain event, they had (2) 75hp motors with grounding rings exposed to water in the small basement mechanical room. Upon checking stock, delivery of new motors equipped with an internal grounding brush would be 5 to 6 weeks. As the motors are being operated by VFD’s, the customer wanted some form of protection against common mode current which could lead to bearing fluting and motor failure. Horner Salesperson Joseph Motz took the opportunity to present the Cool Blue and NaLA inductive absorbers to the [...]

University Flood and VFD Protection2022-01-26T22:56:39-05:00

52 to 2 Amps 1500 HP DC Drive Project With CoolBLUE

In September Horner was called out to a rubber manufacturer in Tennessee to measure common mode currents on a 1500HP DC Drive. The drive end gearbox had just failed. It was found that they had bearing fluting that went through the DC motor into the shaft of the gearbox and into the bearing. The DC drive was connected to the gearbox and that gearbox was connected to a mixer. It mixed raw rubber for the plant.  They measured that the amps were destructive and could cause damage by bearing fluting in the future and they would have the same problem all [...]

52 to 2 Amps 1500 HP DC Drive Project With CoolBLUE2019-09-18T15:36:46-04:00
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