9.2 Low Pressure
System fails to meet minimum pressure
9.3 High Flow
POSSIBLE CAUSE
POSSIBLE CAUSE
POSSIBLE SOLUTIONS
POSSIBLE SOLUTIONS
Flow rate exceeds pump capacity, preventing
it from reaching required discharge pressure
Leak in distribution piping
Insufficient inlet water
Incorrect fault settings
Defective sensor wiring
Defective pressure trasmitter
VFD Failure
Break/leak in the discharge network
Incorrect fault settings
Defective sensor wiring
Defective flow sensor/meter
Use the Trend Log to identify the usage occurring at the time of the Fault.
Faults that repeatedly occur at the same time of day indicates that peak system
demand exceeds pump capacity.
If possible, stagger the demand using an irrigation scheduler.
Use a flow sensor/meter to measure the flow rate.
If the pump operates at or above design flow, but fails to adequately pressurize, then
there is a possible leak in the discharge network.
Locate and repair any leaks in the discharge piping in network.
Make sure the inlet isolation valve is completely open.
Inspect water source.
Use the Trend Log to determine if the fault occurs while the system is operating at
design flow & pressure.
Inspect and adjust the Pressure Setpoints, including the PSI Setpoint, and/or high and
low-pressure alarm settings.
Repair or replace sensor wiring.
Compare pressure transmitter data (via HMI) with the discharge pressure gauge.
A significant difference between readings indicates either an incorrectly scaled, or
failed pressure transmitter.
The replacement pressure transmitter must have an appropriately scaled 4-20mA
output signal.
Determine if the motors are running correctly at full capacity.
Contact VFD manufacturer, or PPS for support.
Inspect piping network for leaks/breaks.
Repair leaks or breakage in the piping network.
Use the Trend Log to determine if the fault occurs while the system is operating at
design flow & pressure.
Inspect and correct the High Flow Fault setting.
Repair or replace sensor wiring.
Replace with flow sensor/meter with appropriately scaled Pulse output signal.
Precision Pumping Systems
•
GoPPS.com
•
6515 Business Way, Boise, ID 83716
•
208.323.5300
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