Yaskawa iQpump Controller Programming Manual - Manual (Page 165)

YASKAWA TM.iQp.07 iQpump Controller Programming Manual 165
■
No-Flow Detection Basic Operation
The iQpump drive can be configured for a no-flow detection condition. The no-flow detection function of the iQpump drive is an
advanced feature for all pumping applications. The typical applications for this function are submersible and booster station pumps.
The programming of the No-Flow Activation Level (P2-11) will activate the no-flow detection function. The drive will monitor the motor
rpm and if the motor rpm falls below the No-Flow Activation Level (P2-11) and the No-Flow Detection Bandwidth (P2-12), the no-flow
process is activated.
The drive will check for system response by monitoring the motor rpm for a time specified by the No-Flow Detection Time (P2-13). If the
motor rpm is within the bandwidth programmed in P2-12 after the time specified by P2-13, the setpoint will be lower by the value
programmed in the No-Flow Setpoint Compensation (P2-16). The drive will wait for the system to stabilize for the time programmed in
the No-Flow Stabilization Time (P2-14).
After the time programmed in P2-14 has elapsed, the setpoint is returned to the original value. The drive will again wait for the system to
stabilize for the time programmed in P2-13. If the time programmed in P2-13 has elapsed, the drive will continue to monitor the feedback
level. If the feedback level falls within the No-Flow Delta Feedback Level (P2-15) for a time programmed in No-Flow Feedback Delay
Time (P2-17), the drive will enter a “sleep” mode after the P2-13 time elapses.
Figure 1.118
Figure 122.
TIME
Motor RPM
P2-12 No-Flow Detection
Bandwidth
P2-13 No-Flow
Detection Time
Decrease Set-Point
by P2-16 Setting
P2-14 No-Flow
Stabilize Time
Set-Point – P2-16
P2-13 No-Flow
Feedback Delay Time
Set-Point
Set-Point
P2-15 No-Flow Delta
Feedback Level
Feedback Signal
Auto Mode Run No-Flow Detected
1
3
2
Monitor Motor RPM
4
Increase Set-Point by
P2-16 Setting
5 6
Output Frequency
P2-11
No-Flow
Activation
Level
0 Hz
Fmax
No-flow detection is active below P2-11 Level
0 RPM
P2-17 No Flow
Note: Sleep function P2-02 is disable (P2-02 = 0)