Yaskawa iQpump Manual Supplement - Manual (Page 31)

10 iQpump MEMOBUS/Network Operation
YASKAWA TM.iQp.10 iQpump Technical Manual Supplement 31
‹ Flow Meter
Certain multiplex pump systems require staging/de-staging based on the flow rate. The iQpump Controller offers a
dedicated set of parameters to operate multiplex pump systems based on flow control.
„ Multiplex Pump System Operation
Flow Rate Staging: Set P9-08 (Add Pump Mode) to 3: Flow Meter.
This mode monitors the Flow Rate to determine if staging is needed. If the Flow Rate of the lead iQpump Controller rises
above the Flow Staging level (no. of pumps running times P9-41) for the time set in P9-11, the drive will issue a network
stage request if an iQpump Controller is available to run.
De-staging: Set P9-12 (Remove Pump Mode) to 3: Flow Meter.
This mode monitors the Flow Rate to determine if de-staging is needed. If the flow rate of the lead iQpump Controller
falls below the Flow De-Staging level ((no. of pumps running - 1) x P9-42) for the time set in P9-15, a de-stage request is
issued if two or more iQpump Controllers are running on the network.
NOTICE: Using Fixed Speed Lag Drive mode P9-05 = 0 in conjunction with Flow Meter Staging (P9-08 = 3) or Flow Meter De-staging
(P9-12 = 3) could result in an unstable system depending on the system and the parameter settings.
Example:
If P9-41 Add Flow Rate Level set to 80.0 GPM, then the 2nd pump is called to run when the flow rate rises above
80.0 GPM. The 3rd pump is called to run the flow rate rises above 160.0 GPM and the 4th pump is called when the
flow rate rises above 240.0 GPM.
Example:
If P9-42 = 60.0 GPM, then the 4th pump is de-staged when flow rate falls below 180.0 GPM. The 3rd pump is de-
staged when the flow rate falls below 120.0 GPM (gallons per minute ) and the 2nd pump is de-staged when the
flow rate falls below
60.0 GPM.
Flow Meter
Outlet
Pressure
Transducer
Inlet
Pump 2 Pump 3
Network
Pump 1
iQpump 2 iQpump 3 iQpump 1
A1
A2
4-20mA
0-10V
Flow Pressure