Omron Q2A Series Technical Manual page 775

terminal set for oH Pre-Alarm Reduction Limit [H2-01 to H2-03 = 4F] activates. When the alarm is not output
during deceleration, the drive accelerates until it is at the frequency reference that was applicable before the alarm
was turned off. Figure 12.139
frequency.
Output frequency
f
ref
f × (L8-19)
ref
2
f × (L8-19)
ref
3
f × (L8-19)
ref
4
f × (L8-19)
ref
oH Alarm count
Multi-function
Digital Output Terminal
H2-01 through H2-03 = 4F
Figure 12.139 Drive Operation at a Decreased Output Frequency when the Overheat Alarm is Output
■
L8-05 In PhaseLoss Selection
No.
Name
(Hex.)
L8-05 In PhaseLoss Selection
(04B1)
0 : Disabled
1 : Enabled
The drive measures ripples in DC bus voltage to detect input phase loss.
The drive detects phase loss when power supply phase loss occurs or the main circuit capacitor becomes unusable,
which causes PF [Input Phase Loss] to show on the keypad.
Disable the detection of the input power supply phase loss function in these conditions:
• During deceleration
• The run command is not input
• The output current is less than 30% of the drive rated current.
■
L8-07 Out PhaseLoss Selection
No.
Name
(Hex.)
L8-07 Out PhaseLoss Selection
(04B3)
Note:
The drive can incorrectly start output phase loss detection in these conditions:
• The motor rated current is very small compared to the drive rating.
• The drive is operating a PM motor with a small load.
0 : Disabled
1 : 1PH Loss Det
If the drive loses one output phase, it will trigger LF [Output Phase Loss].
The output turns off and the motor coasts to stop.
2 : 2/3PH Loss Det
If the drive loses more than one output phase, it will trigger LF [Output Phase Loss].
SIEPYEUOQ2A01A AC Drive Q2A Technical Manual
shows the output of the alarm and the drive operation at a decreased output
10 s 10 s 10 s 10 s
oH
Alarm
oH Alarm
oH
Cancel
Alarm
oH
Alarm
1 2 3
V/f CL-V/f OLV CLV AOLV
Sets the function to enable and disable input phase loss detection.
V/f CL-V/f OLV CLV AOLV
Sets the function to enable and disable output phase loss detection. The drive starts output phase
loss detection when the output current decreases to less than 5% of the drive rated current.
10 s 10 s
oH Alarm
Cancel
4 5 6
Description
OLV/PM AOLV/PM CLV/PM EZOLV OLV/PM
Description
OLV/PM AOLV/PM CLV/PM EZOLV OLV/PM
12.8 L: PROTECTION
10 s
oH
Alarm
Time
10
ON
Default
(Range)
1
(0, 1)
Default
(Range)
0
(0 - 2)
775
12