Frequently Asked Questions
Proper Motor Lubrication
According to EASA, the motor component with the highest failure rate is the bearing. Of all the different types of motor failures, 51% of these failures are bearing failures. If bearings are cared for properly, this 51% number could be significantly reduced…
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Improper Belting – How to identify and correct
Electric motor belting, while often considered a standard and cost-effective procedure, if not applied properly can quickly destroy a motor and the equipment it is driving. There are several warning signs that indicate an improper belting application. If identified early, these simple signals can help save a customer’s motor and reduce costly downtime…
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Alignment Basics – Part One
Misalignment is one of the most common faults found in rotating equipment. Understanding how to properly diagnose and correct for misalignment in plant equipment and how to deal with common pitfalls while out in the field is essential in doing the job right the first time…
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Alignment Basics – Part Two
In theory, machine alignment is a very straightforward process. With some type of measuring device extended across the coupling, the shafts are rotated to several positions (at least three) to determine the relative position between them…
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Winding Failures – Which are covered under Warranty?
Through detailed analysis of the motors returned under Emerson Motor Technologies’ NEMA Winding Failure Return Program, we identified that contributors to some motor failures are application related. Our intent is to help identify application errors so we can prevent the customer from experiencing repeat failures. Improper installation and use of a motor can invite water damage, overloads, inadequate ventilation and other conditions that can severely damage a motor. These are not defects in workmanship or material covered by our warranty…
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Shaft Voltage/Current – Causes and Prevention
In the past few years, there has been a significant increase in motor problems associated with shaft voltages and currents. Voltage discharge from current passing through the bearings can cause the bearings to be damaged or fail if not properly insulated…
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Internal Condensation – Causes and Prevention – Space Heaters Trickle Voltage
Internal condensation is a natural, but extremely damaging condition that can occur in an electric motor. If left unchecked, condensation can lead to swift motor failure. But with a few preventative measures and a little insight,
a motor can be protected from this force of nature…
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Winding Thermal Protection – Effects of Excess Temperature, Thermostats, and RTD’s
Providing winding protection is providing protection against excessive temperatures will help to extend the life of the motor. Excessive winding temperature can permanently damage the winding, greatly reducing winding life (see chart) and can cause complete winding insulation breakdown and failure. Downtime in many motor applications isare prohibitive and a good monitoring system is essential to minimizinge costs which can be incurred as a result of downtime. A complete protection system for a winding is designed to remove the motor from the line when any of the following conditions occur …
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Wye Start/Delta Run 101
As motor manufactures become more aggressive to capture a growing global market, connection schemes in polyphase induction motors are becoming more universal. One method called Wye/Delta, or commonly referred to as Wye Start/Delta Run, is becoming popular with domestic manufacturers selling abroad. This technique of starting the motor wired in a Wye connection, and later switching to a Delta Run connection, will dramatically reduce the current demand on a power distribution system. In areas where utility power is limited or over burdened, this system can reduce brown outs and severe voltage drops when a motor is started…
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Reversing the Direction of Rotation on TEFC Motors
Emerson Motor Technologies integral horsepower totally enclosed, fan cooled (TEFC) motors are equipped with one of three types of external cooling fans…
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Cooling Tower Guide
U.S. Motors has been manufacturing motors for cooling tower applications for many decades. Our experience over that time has led to the development of our new Cooling Tower Duty Motor. This new motor is enhanced with many features specifically designed to address the rigors of the cooling tower environment, including high moisture…
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