high frequency output vfd variable frequency drive & dynamic brake for lathe & mill

We often receive inquiries for variable frequency drives that are capable of high frequency output. Spindle applications such as CNC equipment generally use a high frequency output, up to 400Hz.

Customers often have trouble locating the proper product for these applications. Precision Electric offers a few different options for these type of applications. Our number one recommended product for high frequency output applications is the Lenze/AC Tech SMV Drive.

The SMV drive is designed for several types of applications, including high frequency output. The standard maximum output on many variable frequency drives is 60 -120 hz. The Lenze/AC Tech SMV has capabilities from 0-400hz, right out of the box. We also offer other Lenze/AC Tech products that have a high frequency output option; such as the Lenze/AC Tech MC series and Lenze/AC Tech SCF series drives. However, if you need either an SCF or MC series drive with high frequency output, you must specify that you need the high frequency option. The SCF and MC series products do not come factory equipped with the high frequency option unless specified when your order is placed.

Machine Tool applications such as the spindle on a CNC machine often run their equipment off of high frequency inverters. Typically dynamic braking kits are required when using high frequency output on this equipment.

When CNC machines are running at high speeds the inertia of the spindle causes the motor to become a generator once the stop button is engaged. Voltage generated from the motor goes back onto the DC bus in the drive. This often will cause the drive to trip on an “over bus fault”. This problem is addresed by adding a dynamic brake kit to the drive. The dynamic brake switch will turn on when the bus voltage reaches a preset level to disapate this excess energy across a set of resistors. This will prevent the drive from faulting. The required resistor wattage is determined by the inertia of the load and often requires more wattage than a standard dynamic brake kit will offer. The expert sales staff at Precision Electric will assist you when selecting a drive/brake package for these applications.

RyanChamberlin
Inside Sales, Customer Support
[email protected]