Yaskawa iQpump Programming Manual - Manual (Page 151)

YASKAWA TM.iQp.02 iQpump Drive Programming Manual 151
If P3-01 = 2: Output Frequency + Feedback Level
The de-staging (turning OFF) of the auxiliary pump occurs when the output frequency drops below the level programmed in the Pump 3
Frequency Shutdown Level (P3-10) or Pump 2 Frequency Shutdown Level (P3-09) and the difference (delta) between the system’s
feedback level minus setpoint has exceeded the level programmed in the Shutdown Pump Delta Level (P3-05) for the time programmed
in the Shutdown Pump Delay Time (P3-06).
The auxiliary pumps will be added by the control of the multi-function digital output contact closure (H2-xx = 40 and 41).
■
P3-06 Shutdown Pump Delay Time
Setting Range: 0 to 3600 sec
Factory Default: 5 sec
The de-staging (turning OFF) of the auxiliary pumps will occur after the time delay programmed in the Shutdown Pump Delay Time (P3-
06) has elapsed. The time delay will occur prior to de-staging of the auxiliary pumps.
The Shutdown Pump Delay Time (P3-06) works in conjunction with iQpump drive Multi/Maximum Level (P3-02) and Add Pump Delta
Level (P3-03).
Refer to Lead-Lag Control (P3-01) for further description of de-staging of the pump system.
■ P3-07 Multi Pump Setpoint Increase
Setting Range: 0.0 to 6000.0
Factory Default: 0.0
The iQpump drive can be configured for multiplex pumping operation. The multiplex pumping operation can have the system setpoint
increased each time a pump is staged (turned ON) by programming the amount to be increased into the Multi Pump Setpoint Increase
(P3-07). The system’s setpoint will be lowered by this amount when each pump is de-staged (turned OFF). Refer to Figure 120 below.
The units for this parameter are determined by the System Units (P1-02).
Example: Constant Pressure System
System Setpoint: 80PSI
Pressure Transducer: 150PSI
Multi Pump Setpoint Increase: 4PSI
Pump 1 (Running) Setpoint = 80PSI
Pump 1 + Pump 2 (Running) Setpoint = 84PSI (80PSI + 4PSI)
Pump 1 + Pump 2 + Pump 3 (Running) Setpoint = 88PSI (80PSI + 4PSI + 4PSI)
CAUTION
Do not program this level too close to the system’s setpoint.
If the level is too close to the setpoint, excessive cycling of the pump system may occur.