SYMPTOM

CAUSE

ACTION

System won't start

ESD Button Pushed

Check that all ESD buttons are in their "OUT" position.  Press 'RESET' Button

Main Feeder Protection Tripped

Check feeder protection for blown fuse or tripped circuit breaker.  Check wiring for faults.

Motor Overload Tripped

Check overload relays for flag indication.  Press overload 'RESET' Button.  Check overload setting and match to motor FLA, if set above motor FLA.  Check pump for maintenance.

PLC in 'Stop' mode 

Check the position of the Run/Stop switch on PLC and toggle from RUN to STOP and back to RUN

If problem persists, contact LWR.

Motor won't run in HAND or AUTO

ESD Button Pushed

Check that all ESD buttons are in their "OUT" position.  Press 'RESET' Button

Main Feeder Protection Tripped

Check feeder protection for blown fuse or tripped circuit breaker.  Check wiring for faults.

Motor Overload Tripped

Check overload relay for flag indication.  Press overload 'RESET' Button.  Check overload setting and match to motor FLA, if set above motor FLA.  Check pump for maintenance

Motor Thermistor Opened

Allow motor to cool and try again.  If thermistors open, check system voltage, and motor current.  If ok, check pump for maintenance.

PLC in 'Stop' mode 

Check the position of the Run/Stop switch on PLC and toggle from RUN to STOP and back to RUN

If problem persists, contact LWR

Motor won't run in AUTO

ESD Button Pushed

Check that all ESD buttons are in their "OUT" position.  Press 'RESET' button.

Main Feeder Protection Tripped

Check feeder protection for blown fuse or tripped circuit breaker.  Check wiring for faults.

Motor Overload Tripped

Check overload relay for flag indication.  Press overload 'RESET' button.  Check overload setting and match to motor FLA, if set above motor FLA.  Check Pump for maintenance.

Motor Thermistor Opened

Allow motor to cool and try again.  If thermistors open, check system voltage, and motor current.  If ok, check pump for maintenance.

PLC in STOP mode

Check the position of the RUN/STOP switch on PLC and toggle from RUN to STOP and back to RUN.

Alarm Condition Exists

Clear alarm condition, restart unit.  If alarm occurs again, check system adjustment.

If problem persists, contact LWR.

Motor cycles on and off

Motor Overload Tripped

Check overload relay for flag indication.  Press overload 'RESET' Button. Check to see if relay set to automatically reset.  Check overload setting and match to motor FLA, if set above motor FLA.  Check pump for maintenance.

Motor Thermistor Opened

Allow motor to cool and try again.  If thermistors open, check system voltage, and motor current.  If ok, check pump for maintenance.

If problem persists contact LWR

Water/Chemical on Floor

Piping leak

Find leak and repair.

Vessel leak 

Find leak and repair.

Pump leak

Diagnose point of failure (seal, bearing) and repair as per OEM manual.

If problem persists, contact LWR.

System Performance Reduced

System out of adjustment

Adjust valving to balance flow through the system.

Adjust chemical dosing.

Perform jar test to identify ideal chemistry. If more than 5% above or below anticipated dose, ensure proper polymer makedown.

If problem persists contact LWR

Pump flow is reduced or zero when pump is running

Restriction in line

Ensure all valves on proces piping are open.

Check for pressure building in discharge line. If pressure is increasing, disassemble discharge piping after pressure gauge to identify blockage. If no pressure, disassemble suction piping and discharge piping before pressure gauge to identify blockage.

Incorrect VFD parameters

Use VFD OEM manual to identifty motor nameplate paramter settings and verify they match the motor nameplate.

Improper motor functioning

Check motor rotation.  If motor is running backwards reverse any two motor leads to change direction.

If problem persists, disassemble pump to determine failure.

If problem persists, contact LWR

Pump is flowing but no flow is registered on HMI

Analog error

See analog error troubleshooting.

Flow meter error displayed

Check code in OEM manual.

If problem persists contact LWR

Analog Device Error

Device has no power

Consult single line diagram and ensure main power fuse for device is closed and intact.

Analog input card has no power

Consult single line diagram and ensure analog input card fuse is closed and intact.

Analog input channel has no power

Consult single line diagram and ensure the analog input channel for the associated device is closed and intact.

Corrosion on wire terminals.

Disconnect device from power at the control panel. Starting from the device end, disconnect ±24V wires and clean terminals with a stiff wire brush. Cut and strip back wires and replace.

If problem persists, contact LWR

Poor floc formation

Improper floc mixing

Conduct mixing speed optimization as per "Flocculation Tank" chapter procedure.

Incorrect chemistry dose

Verify chemical pumps are operating correctly.

Check all chemical check valves for blockages.

Ensure proper polymer makedown procedures are followed.

Perform jar test to identify ideal chemistry dose.

If problem persists, contact LWR.

Screw Press Hopper Overflowing

Solids too wet

Reduce polymer dose to avoid overdose conditions.

Optimize mixer speed to create the largest, strongest flocc possible.

Too much water entering Screw Press

Decrease spray bar pressure.

Reduce spray bar chain drive frequency.

Pressure wash screen.

If high degree of scale has built up, perform a descaling treatment.

Too much pressure on screw press doors

Reduce the amount of weight on screw press door arms to increase throughput and solids moisture content.

If problem persists, contact LWR.