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 the low speed at which the
drive wakes up.
Set Low-speed timeout [tSL]
Set Low speed [LSP]
Set Sleep Offset Threshold [SLE]
The 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 driver will sleep when the drive runs at low speed for 60 seconds
The drive will wake up when the speed reference 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 Setpoint [rPI] = 500 and Error [rSL] = 30
The drive will wake up when the PID error [rPE] is 30 below the Setpoint
[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 Setpoint [rPI] = 500 and Wake up three. [UPP] = 470
The drive will wake up when the PID Feedback [rPF] = 470.

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