No.

(Hex.)

Name

Description

Default

(Range)

C6-02

(0224)

Carrier Frequency Selection

Sets the carrier frequency for the transistors in the drive.

Determined by A1-02, C6-01, and o2-04

(Determined by A1-02)

Changes to the switching frequency will decrease audible noise and decrease leakage current.

Note:

Increasing the carrier frequency to more than the default setting will automatically decrease the drive current rating.

1
2.0 kHz
 
2
5.0 kHz (4.0 kHz for AOLV/PM)
 
3
8.0 kHz (6.0 kHz for AOLV/PM)
 
4
10.0 kHz (8.0 kHz for AOLV/PM)
 
5
12.5 kHz (10.0 kHz for AOLV/PM)
 
6
15.0 kHz (12.0 kHz for AOLV/PM)
 
7
Swing PWM4 (Audible Sound 1)
 
8
Swing PWM4 (Audible Sound 2)
 
9
Swing PWM4 (Audible Sound 3)
 
A
Swing PWM4 (Audible Sound 4)
 
F
User Defined (C6-03 to C6-05)

Use C6-03 to C6-05 to set detailed setting values.

Note:

  • The carrier frequency for Swing PWM 1 to 4 is equivalent to 2.0 kHz. Swing PWM applies a special PWM pattern to decrease the audible noise.

  • The setting range changes when the A1-02 [Control Method Selection] value changes:

    • 3, 5, 7, 8 [CLV, OLV/PM, CLV/PM, EZOLV]: You cannot set to 7 to A.

    • 4 [AOLV]: You cannot set to 6, 7 to A, or F.

    • 6 [AOLV/PM]: You cannot set to 7 to A, or F.

Table 1. Guidelines for Carrier Frequency Parameter Setup

Symptom

Remedy

Speed and torque are not stable at low speed.

Decrease the carrier frequency.

Speed and torque are not stable at low speed.

Decrease the carrier frequency.

Too much leakage current from the drive.

Decrease the carrier frequency.

Wiring between the drive and motor is too long.

Decrease the carrier frequency.

Note:

If the motor cable is too long, it can be necessary to decrease the carrier frequency. Refer to Table 2 for the wiring distance and decrease the carrier frequency.

Audible motor noise is too loud.

Increase the carrier frequency. Use Swing PWM.

Note:

The default carrier frequency in ND is Swing PWM 1 (C6-02 = 7), with a 2 kHz base. You can increase the carrier frequency in Normal Duty mode, but this will decrease the drive rated current.
Table 2. Wiring Distance

Wiring Distance

Up to 50 m

Up to 100 m

Greater than 100 m

C6-02 [Carrier Frequency Selection]

1 to F (up to 15 kHz)

1 to 2 (up to 5 kHz), 7€

1 (up to 2 kHz), 7€
Note:

When A1-02 = 5 or 6 [Control Method Selection = OLV/PM or AOLV/ PM], the maximum cable length is 100 m (328 ft).