March 2009
Save time and reduce maintenance cost with new Everlink® Connection Technology
TeSys D 40A through 65A contactors and TeSys GV3P manual motor protectors now feature Everlink connection technology.
Specific to Schneider Electric, the Everlink connection technology saves installation time and money by providing a direct connection without the use of an interconnect block while the robust connection eliminates the need for terminal re-tightening. This technology can also compensate for cable conductor creep reducing maintenance time.
They are a UL508Type F tested combination and comply with Type 2 Coordination standards.
Learn more about TeSys D with Everlink connection Technology online or email us at pump@us.Schneider-Electric.com
Energy Analysis Utilizing Variable Frequency Drives
Systems had traditionally been designed with across-the-line contactors for motor control to power mechanical water movers such as Pumps. The output of these systems is controlled by mechanically constricting the flow with throttling valves or damping vanes.
While these methods reduce the flow of water or other fluids, it is very inefficient. In effect, running a system this way is like driving a car with the accelerator pressed to the floor while controlling your speed with the brake.
A variable frequency drive, on the other hand, allows a precise control of motor output, with significant reductions in the power required to handle the load. This comes from the fact that most pumps are variable torque loads. Meaning, the torque required to drive the load changes according to the speed.
The effects that reduced speed has on a variable torque loads are summarized by a set of rules known as the Affinity Laws.
1. Flow produced is proportional to the motor speed.
2. Pressure produced is proportional to the motor speed squared.
3. Horsepower required is proportional the motor speed cubed.
As an example, a VFD running a variable torque load at 80% speed requires about 50% (.8x.8x.8) of the horsepower or Energy required to run it at 100% speed. This reduction of horsepower means that it costs less to run the motor. When these savings are applied over the annual hours of operation, significant savings can be achieved. Pay back period for installing an AC drive are often less then 12-18 months.
The second affinity law shows the effect that this speed reduction has on the pressure that the pump or fan will be able to deliver. This may be a significant consideration in pumping systems. In most pumping applications, the pump speed must be high enough to over come system pressure. This means the minimum pump speed must be considered in the energy savings calculations. If proper care is taken in engineering the application, VFD's can provide significant energy savings for many different installations.
Have you ever wondered how your facility can become more energy efficient? Visit Square D Lean Tools and Register to discover how Schneider Electric products can help you realize true energy savings.
Visit us at: http://www.us.schneider-electric.com/pump
Contact us: Pump@us.schneider-electric.com
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