▶️ STEP A Connections
The sleep function on the VFAS3 is used for energy saving and elongating the lifespan of the motor. This function puts the drive to sleep when there is no demand for mass flow, which would decrease the run time for the motor and prolong the lifespan.
Sleep function over a run cycle
A line graph illustrates the sleep function over a run cycle. The X-axis represents Time (s) and the Y-axis represents Output frequency (Hz). The graph shows the output frequency starting high, decreasing to a lower limit (<LL>), staying there for a period, then increasing again. It indicates 'Run signal [F] or [R]' and 'ON/OFF' states. Specific parameters like <LL> + <F391>, <LL>, <F256>, and <F259> are marked on the graph.
Check Your Work: ✔️ Verify VFAS3 operates under normal condition before programming Sleep function.
Note: Refer to Section 6.9 in the AS3 Instruction Manual (E6582062) for additional information on the Sleep function.
▶️ STEP B Explanation
The Sleep function will automatically decelerate and bring the drive to a stop when programmed conditions have been met.
The drive's Sleep function begins once the output frequency is at the <LL>: Lower Limit frequency programmed.
The drive must continue to run at the <LL>: Lower Limit frequency for the specified time programmed in the <F256>: Run Sleep detection time parameter prior to the drive's sleep cycle.
Once the drive has met these conditions, the screen will display “LStP” during the sleep cycle.
You can also enable a feature with the Sleep function that will automatically stop the drive after a time period programmed in <F259>: Run Sleep detection time at start-up if the output frequency does not increase past the <LL>: Lower Limit frequency due to load error.
This function is cancelled when the frequency command value is over the values of the <LL>: Lower Limit frequency and the <F391>: Sleep detection hysteresis or when the run command is turned OFF.
Check Your Work: ✔️ Check your understanding of the condition required to enable or disable the Sleep function.
▶️ STEP C Programming
1. Program the Lower Limit Frequency
The lower limit frequency will determine the frequency at which the drive will go to sleep.
| Parameter | Description | Default Value | New Value |
|---|---|---|---|
F013 |
LL: Lower Limit Frequency | 0.0 | Choose New LL Value |
2. Program the Sleep detection time
The drive will need to run at the lower limit for the set period of time to go into a sleep state.
| Parameter | Description | Default Value | New Value |
|---|---|---|---|
F256 |
Sleep Detection Time | 0.0 | Choose New Value |
3. Program the Sleep detection hysteresis
(If applicable) This will be the threshold value that will awake the drive from the sleep cycle.
| Parameter | Description | Default Value | New Value |
|---|---|---|---|
F391 |
Sleep Detection Hysteresis | 0.0 | Choose New Value |
4. Program the Sleep detection time at startup
(If applicable) This will automatically stop the drive upon start-up if there is a load issue preventing the drive to ramp past the lower limit frequency.
| Parameter | Description | Default Value | New Value |
|---|---|---|---|
F259 |
Sleep Detection Time at Start-up | 0.0 | Choose New Value |
Check Your Work: ✔️ Verify parameter change was made by verifying new value programmed.
▶️ STEP D Verification
Program the following below.
| Parameter | Description | Default Value | New Value |
|---|---|---|---|
F013 |
LL: Lower Limit Frequency | 0.0 | 20.0 Hz |
F256 |
Sleep Detection Time | 0.0 | 5.0 s |
F391 |
Sleep Detection Hysteresis | 0.0 | 5.0 Hz |
Start at the main operation screen below and follow the steps as shown.
Initial State: Drive is in STOP mode, displaying '32.9Hz', 'Standard Mode', and '0.0 Hz'.
Action: Enable a Forward run command. Increase your frequency reference above the lower limit value.
Intermediate State: Drive is in RUN mode, displaying '30.0Hz', 'Standard Mode', and '30.0 Hz'.
Verification Step 1:
Standard mode display will show "LStP" to indicate the sleep function is active.
Action: Reduce your frequency reference to 20Hz or below.
State: Drive displays 'STOP', '19.4Hz', 'Standard Mode', and 'LStP'.
Action: Increase the frequency reference above 25Hz and above to allow the VFD to break from the sleep function.
State: Drive displays 'RUN', '30.0Hz', 'Standard Mode', and '30.0 Hz'.
Final State: A 'Complete' status is indicated.
Check Your Work: ✔️ Verify parameter change was made by verifying new value programmed.
