C6-02: Carrier Frequency Selection

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)

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 (AOLV/PM: 4.0 kHz)

3

8.0 kHz (AOLV/PM: 6.0 kHz)

4

10.0 kHz (AOLV/PM: 8.0 kHz)

5

12.5 kHz (AOLV/PM: 10.0 kHz)

6

15.0 kHz (AOLV/PM: 12.0 kHz)

7

Swing PWM4 (Audible Sound 1)

8

Swing PWM4 (Audible Sound 2)

9

Swing PWM4 (Audible Sound 3)

A

Swing PWM4 (Audible Sound 4)

B

Leakage Current Rejection PWM

Set this when the wiring distance between the drive and motor is long and there is a fault in the current monitor or the drive detects and alarm because of the effect of a leakage current.

The carrier frequency is equivalent to 2.0 kHz.

F

User Defined (C6-03 to C6-05)

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

Note:

The setting range changes when the A1-02 [Control Method Selection] value changes:
- 5, 8 [OLV/PM, EZOLV]: You can set C6-02 = 1 to 6, B, and F.
- 6 [AOLV/PM]: You can set C6-02 = 1 to 6.
The carrier frequency for Swing PWM 1 is equivalent to 2.0 kHz. Swing PWM applies a special PWM pattern to decrease the audible noise.

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 C6-02 = 7 [Swing PWM1 (Audible Sound 1)], 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	50 m (164 ft) Maximum	100 m (328 ft) Maximum	More than 100 m (328 ft)
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:

If the length of the wire between the drive and an induction motor is longer than 100 m (328 ft), set A1-02 = 0 [V/f].
The maximum wiring cable length between the drive and a PM motor is 100 m (328 ft).
If the cable length between the drive and the motor is too long when A1-02 = 6, set A1-02 = 5.