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7.3
Common Functions
- 59
Carrier Frequency Reduction Selection: L8--17 (fot SPEC: F)
User
Change
during
Setting
Factory
Valid Access Levels
User
Constant
Number
Name
during
Opera-
tion
Setting
Range
Unit
Factory
Setting
Open Loop
Vector
Flux Vector
L8-17
Carrier frequency reduc-
tion selection 2
0 to 3
--
1
A
D
Settings
Setting
Function
0
No carrier frequency reduction.
1
With carrier frequency reduction.
2
For factory adjustments.
3
For factory adjustments.
D
If metallic noise (carrier noise) from the motor is a problem when carrier frequency is reduced (less
than 6 Hz), set L8--17 to 0 (no carrier frequency reduction), and L8--19 (OL2 characteristics selection
at low speeds) to 1 (enabled).
D
Do not L8--17 and L8--19 to 0 at the same time when using V/f control open loop vector control.
OL2 characteristics Selection at Low Speeds: L8--19 (for SPEC: F)
User
Change
during
Setting
Factory
Valid Access Levels
User
Constant
Number
Name
during
Opera-
tion
Setting
Range
Unit
Factory
Setting
Open Loop
Vector
Flux Vector
L8-19
OL2 characteristics
selection at low speeds
0 1
--
0
A
A
D
Settings
Setting
Function
0
OL2 characteristics at low speeds disabled.
1
OL2 characteristics at low speeds enabled.
D
When using OL2 to trip at low speeds (less than 6 Hz) despite a light load, set L8--17 to 1 (with carrier
frequency reduction) and L8--19 (OL2 characteristics selection at low speeds) to 0 (disabled).
However, do not set 18--19 to 0 for 400 V class, 185 to 300 kW Inverters.
D
Do not L8--17 and L8--19 to 0 at the same time when using V/f control open loop vector control.
D
Reduce the carrier frequency (C6--01) to 2 kHz when continuously operating at low speeds with heavy
loads when using flux vector control.
7