Maximize Duplex Lift Station Reliability

Electrical distributors, pump dealers, and consultants can be invaluable to customers who cannot economically get 3-phase utility service by recommending a converter which has a history of high reliability over the useful life of duplex pump stations.

The DUO ADD-A-PHASE® autotranformer-capacitor type converter has been engineered for use with duplex pump lift stations. It has two independently adjustable capacitor sections - one for each motor - which operate from a common autotransformer. Since both pumps seldom operate simultaneously, the autotransformer is infrequently operated at over 50% of its capacity, and therefore, has an extremely long life. Each capacitor bank is independent from the other and can be balanced for its pump load.

How do DUO ADD-A-PHASE® converters provide higher reliability than that of a rotary phase converter?
 

With alternating pump cycling typical of duplex pumps, any failure in one of the DUO ADD-A-PHASE® sections leaves the other to operate the pump station until repairs can be made. The probability of failure of both sections simultaneously, rendering the pump station inoperable, is practically zero over the life of the station. Rotary phase converters do not offer this redundancy. With a rotary phase converter, if a bearing freezes or other component fails, the converter goes down, rendering both pumps inoperable.

Automatically operated rotary phase converters have capacitors, relays, timers, and bearings. Failure of one of these components not only prevents the rotary converter from starting but also shuts down the entire lift station. Relying upon a single rotary converter weakens the reliability/redundancy that is built into lift stations by using two independent pumps. The DUO ADD-A-PHASE®, with two independent capacitor sections, maintains this redundancy.

The reason the DUO ADD-A-PHASE® is the converter of choice to power duplex pumps is quite simple - it maximizes duplex pump station reliability.

Briefly, the DUO ADD-A-PHASE® provides these performance benefits:

• Duplex redundancy is maintained due to independent capacitor sections for each pump
• Guaranteed to develop full nameplate horsepower of pumps
• Fully automatic, permitting unattended pump operation
• Low inrush current ...and these cost benefits:
• All units are supplied in NEMA 3R aluminum weather proof enclosures
• Neglible losses can result in greater operating efficiency
• Low maintenance
• Eliminates any need for costly step-up or step-down transformers as the internal autotransformer can provide 208V, 240V, 480V, 575V, or 600V output voltage

We are quite familiar with lift stations as RONK Electrical Industries, Inc. has supplied phase conversion for thousands of such applications over more than 45 years. From our experience as a manufacturer of both multiple-section autotransformer-capacitor converters and rotary converters, we believe the reliability needs of lift stations dictate that duplex pump redundancy not be compromised by non-redundant service.

Pump system integrators and engineers continue to employ proven lift station reliability, uniquely afforded by the two-section configuration, DUO ADD-A-PHASE®, first introduced in 1961 - the longest record of performance in the industry.

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