Frequently asked questions
How do I set up the wake-up function for PID control on the ATV71/ATV61?
FA232029
27 July 2022
Issue:
Understanding PID wake up function
Product Line:
Altivar 61 and 71
Environment:
All models and serial numbers
Cause:
None
Resolution:
There are several methods to consider depending if the thought process is in terms of PID error or PID feedback value. They have the same purpose but the method is different.
The following lists the three ways to configure PID Sleeping/Wake up in menu 1.7 Application Function
1. [SLE] Sleep Offset Threshold (ATV61 only)
2. [rSL] PID wake up Threshold (ATV61 and ATV71)
3. [UPP] PID Wake up Threshold (ATV61 only)
(1) Sleep Offset Threshold [SLE] – Frequency above low speed at which the
drive wakes up.
Set Low speed timeout [tSL]
Set Low speed [LSP]
Set Sleep Offset Threshold [SLE]
Following operation at LSP +SLE for a defined period
Example:
Low speed [LSP] = 20
Low speed timeout [tSL] = 60
Sleep Offset Threshold [SLE] = 10
The drive will sleep when the drive runs at low speed for 60 seconds
The drive will wake up when the speed reference is reaches 30 hz.
(2) [rSL] Restart error Threshold – The difference between the set point [rPI]
and the feedback [rPF].
To wake up the drive, the PID error [rPE] must equal the Restart error
threshold [rSL].
Example:
If Set point [rPI] = 500 and Error [rSL] = 30
The drive will wake up when the PID error [rPE] is 30 below the Set point
[rPI].
(3) [UPP] Restart feedback Threshold – The actual set point at which the drive
will wake up.
To wake up the drive the PID Feedback will be equal to the PID Wake up
Thres [UPP].
Example:
If Set point [rPI] = 500 and Wake up thres. [UPP] = 470
The drive will wake up when the PID Feedback [rPF] = 470.