9.7 Voltage Fault
9.8 Overload
9.11 Discharge Pressure Transmitter Failure
9.9 Underload
9.10 Communication
POSSIBLE CAUSE
POSSIBLE CAUSE
POSSIBLE CAUSE
POSSIBLE CAUSE
POSSIBLE CAUSE
POSSIBLE SOLUTIONS
POSSIBLE SOLUTIONS
POSSIBLE SOLUTIONS
POSSIBLE SOLUTIONS
POSSIBLE SOLUTIONS
Defective supply power
Excessive demand exceeds
motor/pump capacity
Defective sensor wiring
Defective pressure transmitter
Prime Loss (Pump is running dry)
Defective cables connecting controller
to VFD
VFD Error
Incorrect VFD communication protocol
Wait for the system to attempt an auto restart. If the system does not
restart or shuts down again, call a certified electrician for further
diagnosis.
Inspect incoming power for missing or out of balance.
Contact Power Company if incoming power is the issue.
Use the Trend Log to determine if the fault occurs while the system is
operating at design flow & pressure. Make sure demand does not
exceed the motor/pump design capacity.
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.
See Section 6.6 Prime Loss, above.
Repair or replace communication cables.
Power-cycle the VFD:
• Turn OFF Power to the VFD.
• Wait until keypad is powered down.
• Turn ON Power to the VFD.
Change VFD Communication Protocol to STANDARD MODBUS:
• Press the MENU button.
• Scroll to PARAMETERS, press ENTER
• Scroll to SYSTEM CONTROLS, press SEL
• Scroll to 1611 PARAMETER VIEW, press EDIT
• Scroll to LONG VIEW, press SAVE
• Press EXIT to return to PARAMETERS MENU
• Scroll to 98 OPTIONS, press SEL
• Scroll to 9802 COMM PROT SEL, press EDIT
• Scroll to STD MODBUS, press SAVE
• Press EXIT 3 times to return to Main Menu
