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“B” Group: Fine Tuning Functions

Miscellaneous Settings

Configuring

Drive Parameters

 

 

The miscellaneous settings include scaling factors, initialization modes, and others. this section covers some of the most important settings you may need to configure.

B_83: Carrier frequency adjustment – The internal switching frequency of the inverter circuitry (also called the chopper frequency). It is called the carrier frequency because the lower AC output frequency of the inverter “rides” the carrier. The faint, high-pitched sound you hear when the inverter is in Run Mode is characteristic of switching power supplies in general. The carrier frequency is adjustable from 500 Hz to 16 kHz. The audible sound decreases at the higher frequencies, but RFI noise and leakage current may be increased. Refer to the specification derating curves in Chapter 1 to determine the maximum allowable carrier frequency setting for your particular inverter and environmental conditions.

NOTE: When DC braking is performed, the inverter automatically holds the carrier frequency at 1 kHz.

NOTE: When the inverter is in sensorless vector mode, use B_83 to set the carrier frequency greater than 2.1 kHz for proper operation.

NOTE: The carrier frequency setting must stay within specified limits for inverter-motor applications that must comply with particular regulatory agencies. For example, a European CE-approved application requires the inverter carrier to be less than 5 kHz.

B_84, B_85: Initialization codes – These functions allow you to restore the factory default settings. Please refer to “Restoring Factory Default Settings” on page 6–8.

B_86: Frequency display scaling – You can convert the output frequency monitor on D_01 to a scaled number (engineering units) monitored at function D_07. For example, the motor may run a conveyor that is monitored in feet per minute. Use this formula:

Scaled output frequency (D_07) = Output frequency (D_01) ⋅ Factor (B_86)