Yaskawa AC Drive-P1000 Industrial Fan - Manual (Page 186)

Bias
Output
frequency
Bias is added to frequency
reference and reset to 0
Up 2 command
Frequency
reference
5 s
5 s
Figure 5.31 Up/Down 2 Example with Reference from Digital Operator and d4-01 = 1
• Up/Down 2 with frequency reference from input sources other than the digital operator
When a Run command is active and the Up/Down 2 command is released for longer than 5 s, the bias value will be saved
in parameter d4-06. When restarting after the power is switched off, the drive will add the value saved in d4-06 as a bias to
the frequency reference.
Bias
Output
frequency
Up 2 command
d4-06 value
5 s
Bias is saved in parameter d4-06
5 s
Figure 5.32 Up/Down 2 Example with Other Reference than Digital Operator and d4-01 = 1
Note: Set the limits for Up/Down 2 properly when using d4-01 = 1 in combination with the Up/Down 2 function. Refer to d4-08: Frequency
Reference Bias Upper Limit (Up/Down 2) on page 188 and Refer to d4-09: Frequency Reference Bias Lower Limit (Up/Down 2) on
page 188 for details on the limit settings.
Clearing the Saved Value
Depending on which function is used, it is possible to clear the saved frequency reference value by:
• Releasing the input programmed for Acceleration hold.
• Setting an Up or Down command while no Run command is active.
• Resetting parameter d4-06 to zero.
Refer to d4-06: Frequency Reference Bias (Up/Down 2) on page 188 for details.
n d4-03: Frequency Reference Bias Step (Up/Down 2)
Sets the bias added to or subtracted from the frequency reference by the Up/Down 2 function.
No. Parameter Name Setting Range Default
d4-03 Frequency Reference Bias Step (Up/Down 2) 0.00 to 99.99 Hz 0.00 Hz
The operation depends on the set value:
Setting d4-03 = 0.00 Hz
While the Up 2 or Down 2 command is enabled, the bias value is increased or decreased using the accel/decel times determined
by parameter d4-04.
5.4 d: Reference Settings
186 YASKAWA SIEP YAIP1U 01B AC Drive - P1000 Technical Manual