The drive uses the delay time set in parameter L8-40 and a hysteresis of 12% when switching the carrier frequency back to
the set value.
n
L8-40: Carrier Frequency Reduction Off-Delay Time
Sets a hold time before returning to the original carrier frequency setting after the carrier frequency has been temporarily
derated as determined by L8-38. The carrier frequency reduction function is disabled when this value is 0.00 s.
No.
Name
Setting Range
Default
L8-40
Carrier Frequency Reduction Off-Delay Time
0.00 to 2.00 s
0.50 s
n
L8-41: High Current Alarm Selection
Triggers a high current alarm (HCA) when the output current exceeds 150% of the drive rated current.
No.
Name
Setting Range
Default
L8-41
High Current Alarm Selection
0, 1
0
Setting 0: Disabled
No alarm is detected.
Setting 1: Enabled
An alarm is triggered when the output current exceeds 150% of the drive rated current. A digital output set for an alarm
(H2-
oo
= 10) will close.
n
L8-55: Internal Braking Transistor Protection
Enables and disables protection for the internal braking transistor.
No.
Name
Setting Range
Default
L8-55
Internal Braking Transistor Protection
0, 1
1
Setting 0: Disabled
Disable braking transistor protection when not using the internal braking transistor, including the following instances:
• When using a regen converter such as DC5.
• When using a regen unit such as RC5.
• When using external braking transistor options like CDBR units.
• When using the drive in common DC bus applications and the internal braking unit is not installed.
Enabling L8-55 under such conditions can incorrectly trigger a braking transistor fault (rr).
Setting 1: Enabled
Enable L8-55 when connecting a braking resistor or a braking resistor unit to the drive built-in braking transistor.
Models 5A0003 to 5A0052 come with a built-in braking transistor.
n
L8-97: Carrier Frequency Reduction Rate during oH Pre-Alarm
Derates the carrier frequency to the level set to L8-39 during oH pre-alarm.
No.
Name
Setting Range
Default
L8-97
Carrier Frequency Reduction Rate during oH Pre-Alarm
0, 1
0
Setting 0: Disabled
Setting 1: Enabled
1.8 L: Protection Functions
122
YASKAWA SIEP YAIZ1U 03B YASKAWA AC Drive – Z1000 Programming Manual
Summary of Contents for Z1000 CIMR-ZU*A Series
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