Category Archives: Technical Tips

Franklin Electric’s Pump Selector Now Multilingual

Posted on by copywriterfele

As the first quarter begins, we would like to take this opportunity to reintroduce the Irrigation Pump Selector. By entering in a few pieces of information like design points, fluid properties, and motor sizing, Pump Selector can quickly search across Franklin’s FPS high capacity centrifugal and submersible pump catalog and find the appropriate product for you. It not only provides pump recommendations, but it can also create PDF versions of pump reports, offer cost analysis, develop VFD application curves, and much more!

Both the desktop and online versions of the Irrigation Pump Selector have gone through significant updates to include the latest Franklin products. These updates include, but are not limited to:

  • 4 x 6-13 h
  • Self-priming pumps
  • 6- & 8-inch SR
  • 6-inch, 500 gpm STS

Language support has also been added to both versions. The desktop version now supports English, Spanish, French, German, and Italian, while the online version supports English, French, and Spanish.

New this year, the Pump Selector desktop version is available for download. Download the Irrigation Pump Selector by clicking on the Pump Selector download button located just below the online version of the Pump Selector or click here to go directly to the Pump Selector website. Continue reading →

AIM Manual VFD Update

Posted on by copywriterfele

Variable Frequency Drive Submersible Motor Requirements

We strive to improve and maintain quality standards that exceed our customer expectations. To address the growing large submersible motor markets, the Franklin Electric Submersible Application Installation Maintenance (AIM) manual Variable Frequency Drive (VFD) section has been updated to stress the need for an additional output filter to be purchased for virtually all large submersible motor applications.

The Variable Frequency Drive Submersible Motor Requirements section of the AIM manual is available to download from the Franklin Electric website.

Additionally, a VFD Output Filter Supplement is available with commentary on why the need for an output filter on submersible motors is different from those for aboveground motors. This supplement is informational only and is not included in the AIM manual. To obtain a copy, please contact your local Franklin Electric Representative.

If you have any further questions concerning the AIM manual update or VFD Output Filter Supplement, please contact Franklin Electric’s Technical Service Hotline at 800.348.2420 or hotline@fele.com.

VFD submersible motor requirements AIM manual update page 40 and 41

Amps Vs. Watts – What’s the Operating Cost?

Posted on by leslie5677

One of the more confusing things about electricity is how it’s measured and how we pay for it. We would like to take a moment to clear up any misunderstandings about electrical power, especially in terms of calculating the electrical cost of operating a submersible pump. We all pay for the Kilo-watt hours on our electrical bill.

kW hours are calculated by multiplying the watts time hours of operation, all of this divided by 1000 to equate to kW hours.

kW-Hr = (Motor Watts * Hours of operation)/1000.

2Wire 1Ø Motor
SF Watts SF AMPS
Hp Volts Franklin Others Franklin Others
1/2 115 960 1088 12 9.5
1/2 230 960 1073 6 4.7
3/4 230 1310 1459 8 6.4
1 230 1600 1900 8.6 9.1
1 1/2 230 2180 2520 13.1 11
3 Wire 1Ø Motor
SF Watts SF AMPS
Hp Volts Franklin Others Franklin Others
1/2 115 960 916 12 12.6
1/2 230 960 1033 4.3 4.9
3/4 230 1310 1381 5.7 6.3
1 230 1600 1672 7.1 7.2
1 1/2 230 2100 2187 11.5 11.1

With the exception of the 1/2HP 115V 3 W motor Franklin watts (what we pay for) are lower than the competitive motor.  Many people assume that amp draw is the key factor, when in fact, the real issue is how well you convert the amps to output, otherwise known as efficiency of operation.

Assuming the average household consumes 500 Gal of water per day, using a 20 GPM 2W 1.5HP unit pump, this would require 25 minutes of operation per day or 750 minutes or 12.5 hours of operation per month. Assuming a kW cost of $0.10/kW-Hr, it would cost 2180*12.5*0.1/1000=$2.73, the physical cost, to operate an Franklin Electric equipped unit or $3.15 for the competitive unit.

Kilowatts are a measure of power, amps are a component of power and the other key is the materials and efficiencies associated with converting the power to rotational energy.  So, next time your customer wants to know how much it costs to operate their private water system, you can show them the figures and assure them that a submersible pump from Franklin Electric is one of the best deals around.

Best starting torque in the industry

Posted on by leslie5677

Franklin Electric motors have the highest starting torque in the industry. Why does this matter? A motor needs enough force to overcome inertia and friction and start spinning. Without it, nothing moves: not your motor, not your water.

So how does it work? When a water system’s pressure switch closes, power flows to the motor. This energizes the stator and creates a rotating magnetic field that interacts with the rotor.. This causes the rotor to spin, thus turning the shaft and driving the pump.

All of this happens in the blink of an eye and while trying to overcome impeding forces. Friction is the main culprit, and it comes from various sources. These may include:

  1. Debris or mineral deposits lodged between the pump body and impellers
  2. The motor’s internal friction from radial and thrust bearings.
  3. The pump’s internal friction from bearings, wear rings and other points of contact between the impellers and pump housing.
  4. Friction due to misalignment or damage.

Because starting torque plays such a significant role in a motor’s operation, you should be familiar with the design characteristics of the motor you are considering. In North America, you might find the following single-phase design types:

  • 2-wire PSC (Permanent Split Capacitor)
  • 2-wire Split-phase
  • 3-wire CSIR (Capacitor Start Induction Run)
  • 3-wire CSCR (Capacitor Start Capacitor Run)

Starting Torque Chart
Typical Starting Torque of a 1/2Hp Motor

You should also keep in mind that the starting torque of any motor is a function of the voltage available at the motor terminals. In the event of a low voltage condition at start-up which may be due to a supply issue or drop cable size, a 5% reduction in voltage results in a starting torque reduction of nearly 10%. In this case, there is a higher risk that the lower torque PSC motor will not be able to start the pump.

In addition to the higher starting torque of Franklin 2-wire motors, they boast a feature that no other 2-wire motor in the world can claim: reverse impact torque. When starting torque alone is not enough to overcome a bound pump, Franklin’s reverse impact torque feature goes into action. It applies a repetitive forward and backward force to the shaft that results in a “machine-gun” or ratcheting impact. This will break free many bound pumps and allow them to run freely.

The next time you are selecting a motor, consider the importance of starting torque to the quality of your installation. You’ll see that Franklin motors “shake-out” above the rest.