During the past 20 years, the wastewater industry has significantly increased the use of variable frequency drives (VFDs) in wastewater pumping systems. VFDs provide better control of the wastewater flow through pumping stations than constant-speed pumps. Plus, as power costs continue to increase and utilities look for ways to reduce costs, VFDs often provide a great solution.

Variable Speed Drives offer the following advantages over pumps with across-the-line starters:

• Possible power savings depending on the slope of the system head curve and the pump performance curve
• Better for WWTP processes due to the constant flow rate to the plant
• Less likely to overload downstream gravity sewer
• The pumping rate matches the inflow
• Soft start and soft stop feature extends the life of the equipment
• Reduced inrush current and voltage dips
• Easy on pumps, motors, valves, couplings
• Reduced water hammer potential
• Provides flexibility to change pumping rate

Gorman-Rupp’s Pump Control Panels with VFDs are a standard product. Equipment is provided in NEMA 3R steel enclosures with panel heaters and ventilation fans. Panels to include lockable main circuit breaker, Hand-Off-Auto selector switch, elapsed time meter, door-mounted keypad message center (HIM-Human Interface Module), door-mounted disable push button, indicating lights for pump run, VFD fault, and no flow/load. The control panels come standard with Allen-Bradley Power Flex 753 variable frequency drives and are UL and cUL listed.

Panels include logic in the VFD for remote start/stop operation with panel connectors for inputs. The panels are set up for two float inputs (start level and stop level at a preset speed) or a single transducer input (level and pressure). The transducer input allows for variable speed pumping based on the scalable 4-20 mA signal. Dry contacts are provided for monitoring drive run, drive faulted, no flow/load, and torque/power out-of-range alarms. Control panels are available to ship from Gorman-Rupp in four weeks or less.

Gorman-Rupp’s lift station controls are designed to ensure system performance by precisely matching the controls to the pumps and motors. Customers have four choices in liquid level controls when they select a Gorman-Rupp ReliaSource solids-handling pump package. Gorman-Rupp control panels offer simple, reliable performance and are designed for accurate start/stop operation, alternation, level sensors, pump delay, and alarms. Advanced control systems include soft starters or variable frequency drives (VFDs) to manage electric inrush, hydraulic shock, and matching starting and stopping torque-based management and monitoring.

At Envirep/TLC, customer service is not a department; it’s our #1 mission.

As a manufacturers rep, we work with consulting engineers, municipalities, owners, and industries to provide budget pricing, pumping and process designs, and assist in integrating equipment into the project.

Envirep is the manufacturer’s rep for Gorman-Rupp pumps and pump parts in PA, MD, DE, VA, and Washington D.C. Contact Envirep at 717-761-7884 or sales@envirep.com.

By Joshua P. Price, Service Manager at Envirep, Inc.

Gorman-Rupp is the industry leader and innovator in high-quality pump design. At Envirep/TLC, we will help you choose the best Gorman-Rupp^® pump parts for your needs. Our goal is to provide you with easy-to-operate, low-maintenance pump parts to ensure you are as cost-effective as possible.

Envirep/TLC is an authorized distributor of Gorman-Rupp pump products, and we carry a huge inventory of spare parts, so our customers receive the best service possible.

It is always best to use genuine Gorman-Rupp parts when repairing a Gorman-Rupp pump. Gorman-Rupp manufacturers parts to exact tolerances and exact material specifications. Not having the right part can reduce the service life and affect the pump’s life, other parts in the pump, and the pump’s efficiency. Only genuine Gorman-Rupp parts can guarantee that your part will fit perfectly and deliver reliable service for many years.