In the May/June 1997 issue of Franklin Aid, we introduced Franklin’s new 8-inch Severe Duty motor. Since then we have been receiving questions about writing specifications. Below you will find typical specifications for the Severe Duty motor. If you require specifications for Franklin Electric’s water well submersible motors please call our Hotline. Continue reading
One of the most feared phrases in the water well industry is “It’s stuck”.
Every day hundreds, maybe thousands, of submersible motors are removed from wells without incident. However, every once in a while something causes one to hang up or keeps it from being removed.
Some of the common causes are shale or rocks that fall from above the pump and motor. These rocks wedge between the pump or motor and the well casing. They don’t have to be very big, just wedged in the wrong place. Sometimes carefully moving the motor up and down will free the unit. Another common reason for hang-ups is when a safety cable or the drop wire comes loose from the top and coils itself around everything down below. This can happen if the wire is not properly supported. Again moving the motor up and down carefully might free the unit. Continue reading
This issue of Franklin Aid discusses chlorination of water wells only in the context of possible adverse effects to submersible motors if caution is not exercised. This issue is not meant to serve as an all-inclusive procedure for chlorinating wells. This would be impossible since specific requirements and regulations vary by state and locality. For additional information on correct chlorination procedures, please contact your local health department or your State Department of Natural Resources.
Chlorination of new and existing water wells is a common practice in our water systems industry. Chlorination disinfects water supplies and kills bacteria, which may be present in the well or was introduced into the well during normal drilling and casing operations. Ideally a water well should be chlorinated without a submersible water system installed, but this is not always practical. Continue reading
In this issue of Franklin AID we will continue to review “Why Submersible Motors Fail”. However, before we do, in the September/October issue on CHECK VALVES, we spoke of a “soft start” in reference to water hammer. Someone asked, “What is a soft start?” A “soft start” is another term commonly used to describe a reduced voltage starter.
Voltage Surges and Spikes:
High voltage surges and voltage spikes are the result of close proximity lightning strikes, opening of power line switch gear, fast current-limiting power line switch gear, or the removal of large inductive loads from the power lines. These spikes and surges can travel to the motor windings, where they attempt to break down the insulation resistance. While Franklin motors can handle voltage surges in the magnitude of 10,000 volts, unfortunately, power surges do not limit themselves to this voltage. This is why a good surge arrestor, capable of multiple hits, is needed for submersible motors without internal arrestors (4-inch single-phase motors have built-in arrestors). Remember, there is little advantage to installing an arrestor unless it is grounded to the water strata. Surge arrestors over the years have also been known as lightning arrestors. While a direct lightning strike of millions of volts to the motor is almost impossible to protect against, voltage surge related motor failures can be prevented with good arrestors and proper grounding. Continue reading
As we look at our submersible motors and their usage, we keep one goal in mind. That goal is quality. Quality products and installations equal long service life and long service life generally equals satisfied customers. Over the years, Franklin has reviewed many motors returned from the field. Along with looking at the returned motor itself, Franklin examines numerous applications and systems, looking for problems which contribute to premature motor failure. In the next few issues of Franklin AID we will share with you some of the ways you can avoid application related problems and get the longest life out of your pump installation.
Although several items in this article apply to single-phase motors and systems, the majority is on three-phase installations. Basically there are three types of motor failures; electrical, mechanical, and mechanical failures that progress into electrical failures. In this issue, we will focus on the electrical side. Continue reading