FAQ #9: Pump System Rotation

Is there an easy way to check rotation of a 3-phase pump system?

Several methods can be used:

Typical: If the shaft is visible, bump the motor or briefly apply power. Normal rotation is CCW for a submersible motor when looking at the motor shaft. If the shaft is not visible, turn on the pump and check pressure and flow. Reversing 2 of the 3-phase power wires makes the motor run in the opposite direction. Best water pressure and flow is typically the correct rotation.
Other options: If the power company can tell you phase A, B and C (not always L1, L2 and L3) and you connect the motor wiring per page 34 of the AIM manual, the motor rotation will be CCW.

Motor rotation meters can be purchased and used. However, this can be confusing.  Rotation meters are generally designed to work with above ground motors, i.e. conveyor belts and blowers, so they typically provide rotation VS the lead end or opposite pulley end of the motor. Since a submersible motor has the lead coming out the same end of the motor as the shaft, if the rotation meter says CW rotation, the submersible motor is really turning CCW.

Pump selector

Through innovation and product expansion over the last several years Franklin Electric has been able to expand into new markets and offer the same complete pumping systems our motors have powered for years. One of the fastest expanding product lines, Industrial and Irrigation (I&I), now offers full water systems.
Franklin Electric turbine pumps, known as the ST and STS Series, are designed for irrigation, farm use, and municipal and commercial applications. Franklin’s 6- and 8-inch large submersible turbines have flow ratings of 100 to 375 gpm for 6-inch pumps, and 225 to 1,000 gpm for 8-inch pumps. These features promote efficiency, abrasive resistance, proven longevity, and corrosion resistance.

Franklin also manufactures large and small radial pumps. The SR Series 6- and 8-inch pumps are built for corrosive water, municipal and industrial applications. These stainless steel submersible pumps come in 70, 100, 150, 240 and 300 gpm flow ratings for 6-inch models, and 400 and 475 gpm for 8-inch models.

Franklin’s high capacity radial 6-inch pumps come in flow ratings from 50 to 125 gpm. This makes the radial pump the most economical pump in the industry for its flow rates and is designed for agricultural, fountain and livestock watering applications.

End suction centrifugal, booster and sprinkler pumps help complete the I&I family of products. These pumps are covered by the D-Series, F-Series, and I-Series, end gun booster, Turf Boss, gas engine, multi-stage booster, and water truck lines, available in flow ratings up to 6,000 gpm. Franklin centrifugal pumps provide complete water systems for applications from irrigation to dewatering and land reclamation. Continue reading

Hotline FAQ: Pressure Tank for Constant Pressure Systems

Do I still need a pressure tank with a Franklin constant pressure system?

Variable Frequency Drive systems including Franklin’s MonoDrive and SubDrive still use a bladder tank but are typically much smaller than one sized for a standard system.

In a SubDrive or MonoDrive installation the tank’s role is to capture water turbulence, not store water. The MonoDrive and SubDrive systems are designed to hold water pressure to plus or minus one psi of the set point. With a switch this sensitive, any water turbulence around the pressure sensor would cause wider pressure swings. The tank’s job is to capture any wave action in the plumbing coming from the pump side, so the water moving around the pressure sensor is smooth and steady.

The gallons per minute, or gpm rating of the pump, determines the size of the tank needed. The tank’s air pre-charge is also different than a conventional system. Please see your installation manual for complete instructions.

See previous frequently asked questions on our FAQ page.