VFD failure cuts capacity at IEUA desalter as supply chain delays threaten year-long repair

VFD failure cuts capacity at IEUA desalter as supply chain delays threaten year-long repairA capacitor fire inside a 10-year-old variable frequency drive has taken a 1.4 MGD reverse osmosis train offline at the Chino 1 desalter, forcing the Inland Empire Utilities Agency to scour the market for scarce replacement parts.

A capacitor failure inside a VFD cabinet disabled one reverse osmosis train, cutting water production by 1.4 million gallons per day.

Full replacement of the high-horsepower VFD faces a lead time of upwards of a year due to ongoing global supply chain constraints.

The 10-year-old unit failed prematurely compared to the standard 12- to 17-year lifecycle for VFDs in the agency's asset management plan.

IEUA staff are currently seeking new or used replacement capacitors from multiple vendors, as the parts cannot be kept in long-term shelf inventory.

The Inland Empire Utilities Agency (IEUA) is grappling with a significant operational disruption at its Chino 1 desalter after a variable frequency drive (VFD) failure took a reverse osmosis (RO) train offline, reducing the facility's production by 1.4 million gallons per day (MGD). During a July 1 workshop meeting, IEUA management reported that a capacitor fire inside the VFD cabinet caused the failure during early morning hours. The drive controls the motor speed for the RO train—a critical operational function due to system pressure fluctuations that prevent the use of a standard, fixed-setting electrical motor as an interim fix. The incident highlights persistent supply chain challenges plaguing the municipal water sector for large electrical equipment. Procuring a complete replacement VFD of this horsepower currently carries a lead time of upwards of a year. To expedite the repair and restore the 1.4 MGD capacity, the agency is actively searching for replacement capacitors, considering both new and used parts from multiple vendors. Staff noted they are even exploring the possibility of borrowing components from other units if compatible parts can be identified. The failed VFD was 10 years old and housed in a clean, air-conditioned environment. Agency staff noted the failure was unexpected, as VFDs typically have a minimum lifespan of 12 years and are scheduled for replacement every 15 to 17 years under IEUA's broader asset management program. While the VFD cabinet undergoes annual preventative maintenance and cleaning, the internal capacitors do not receive separate preventative maintenance. Furthermore, staff explained that spare capacitors cannot be kept in long-term shelf inventory because they have a limited uncharged lifespan and must be maintained and recharged prior to use. The desalter is operated under contract by the Chino Basin Desalter Authority (CDA). While the CDA recently approved the purchase of new membranes for portions of the facility, the immediate bottleneck remains the electrical equipment. IEUA staff confirmed the affected RO train will remain offline until the VFD is repaired, with no firm estimated time of arrival for the required components currently available.