N: Special Adjustments - YASKAWA Varispeed G7 Series Instruction Manual



N: Special Adjustments

The following settings are made with the special adjustments constants (N constants): Hunting prevention,
speed feedback detection control, high-slip braking, speed estimation, and feed forward control.
Hunting Prevention Function: N1
User constants for hunting prevention are shown in the following table.
Con-
stant
Number
Hunting-pre-
vention func-
tion selection
N1-01
Hunt Prev
Select
Hunting-pre-
vention gain
N1-02
Hunt Prev
Gain
Hunting-pre-
vention time
N1-03
constant
*1
Hunt Prev
Time
* 1. Applicable for G7-Series Inverters with software version PRG 1034 and later.
* 2. The factory setting depends upon the Inverter capacity. The value for a 200 V Class Inverter of 0.4 kW is given.
-70
5
Name
Description
Display
0: Hunting-prevention
function disabled
1: Hunting-prevention
function enabled
The hunting-prevention func-
tion suppresses hunting when
the motor is operating with a
light load.
This function is enabled in V/
f control method only.
If high response is to be given
priority over vibration sup-
pression, disable the hunting-
prevention function.
Set the hunting-prevention
gain multiplication factor.
Normally, there is no need to
make this setting.
Make the adjustments as fol-
lows:
• If vibration occurs with
light load, increase the set-
ting.
• If the motor stalls, reduce
the setting.
If the setting is too large, the
voltage will be too suppressed
and the motor may stall.
Set the hunting-prevention
primary delay time in units of
ms.
Control Methods
Change
Setting Factory during
Range Setting Opera-
V/f
tion
0 or 1 1 No A
0.00 to
1.00 No A
2.50
0 to
10 ms
No A
500
*2
MEMO-
Open Open
BUS
V/f Loop Flux Loop
Regis-
with Vec- Vec- Vec-
ter
PG tor tor tor
1 2
A No No No 580H
A No No No 581H
A No No No 582H
Page
6-41
4-29
6-41
6-41