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  How can a variable speed drive (VSD) improve our production?

 And variable frequency drives (VFDs, AC drives) have built in surge protection which include high/ low voltage surges as well as Lightning surges in an effort to prevent electrical burn outs. The pumps speed is controlled to provide optimum performance without overloading the motor making for a longer lasting system.

 One of the biggest questions is what exactly is a Constant Pressure pumping system? This article will unveil some of the mystery surrounding these variable frequency drives (VFDs, AC drives) and Constant pressure submersible pumping systems. 

Case study on use of Variable speed motors in pumping industry. Environmental influence and financial aspects of use of variable speed drives (VSDs, frequency inverters, AC drives).

Concerned project has been carried out on high specifications residential site that was constructed in two phases. In phase 1, the first building has been developed and made ready for occupation. During this period a booster set was installed and sized for the initial part of development.

During phase 2 of the construction, previously installed booster set found to be too small to support both sections of the project. Therefore, second set of pumps had to be fitted and used in order to supply water to the phase 2.

Frequency inverter and the system controller are used for injection molding machine to only pump the oil needed. The system controller monitors the machine's controller and generates a signal that corresponds to the needed volume of hydraulic oil. Thus with these 2 equipments, if the machine does not need the oil, don't pump it in the first place.

The advantages of this system on injection molding machine include energy saving, better repeatability (it is easier for the machine to control the lower volume of oil), quieter machine operation, lower oil temperature, less demand on the cooling tower and less wear and tear on the machine.

Generally the power supplied by the power utilities is fixed-frequency, the pump motors in injection molding machines turn at a fixed speed. If the pump motors are turning at a fixed speed, the pumps are turning at a fixed speed. If the pumps are turning at a fixed speed, they pump a fixed volume of hydraulic oil.

If machines always operated at full capacity (clamp open, close, injection and screw charge at 100% with no cooling time), there would be no problem. However, injection molding machines rarely operate at full capacity. Most injection molding machines pump more oil than they need.

Generally up to 70% of the electricity consumed by injection molding machine is never used in the molding process. It's wasted. The wasted electricity (energy) by injection molding machine brings some problems: heating the machine's hydraulic oil, noise, and wear and tear on the machine's hydraulic system. The hydraulic oil in an injection molding machine gets hot, and would cook if not for a cooling tower.

The end effect is that you pay to pump the oil (with the machine's pump motor), then you pay to cool the oil (with your cooling tower). Thus you need to pay for a high electric bill. Meanwhile you get a hot and noise machine. Surely this is not the desirable result you want. But it's the reality when you are using injection molding machines.

It's said that 40% of all power in Europe and North America is consumed in  the buildings. The biggest share of the energy is consumed in heating, ventilation and air conditioning (HVAC) applications.

In China's power consumption, the power consumption by the buildings accounts for around 32 percent. Yes. The biggest share of that is in heating, ventilation and air conditioning (HVAC) applications too.

The situations of power consumption is similar in other countries and areas. Thus the energy savings potential in HVAC applictions is large.  It is crucial to use all means available to reduce the energy consumption in the building, especially in HVAC applications.

Applications of energy efficiency variable speed drive (vsd, frequency converter):

The most common applications of ariable speed drive (vsd, frequency converter, adjustable frequency drive) are for pumps and fans to balance flows, and meet changing system needs. For example, Variable speed drives (frequency inverters) can be very cost-effective in retrofit or new construction of heating, ventilating, and air conditionin (HVAC) systems. Many heating, ventilating, and air conditionin (HVAC) systems were designed with constant flow pumps and fans that are throttled to meet changing operating conditions.

Variable speed drive (vsd, frequency converter, adjustable frequency drive) is also useful for loads, such as elevators, water and wastewater pumps, boiler fans, cooling towers, cranes and conveyors.

Variable frequency drives (frequency inverters, VFDs, variable speed drives) allow more precise control of processes, such as water distribution, aeration and chemical feed. Pressure in water distribution systems can be maintained to closer tolerances. Waste-water treatment plants can consistently maintain desired dissolved oxygen concentrations over a wide range of flow and biological loading conditions by using automated controls to link dissolved oxygen sensors to variable frequency drives (frequency inverters, VFDs, variable speed drives) on the aeration blowers.

Energy savings from variable speed drives can be significant. Affinity laws for centrifugal pumps suggest that even a small reduction in motor speed will highly leverage the energy savings.

Variable speed drives (frequency inverters, VSDs, VFDs, variable frequency drives) can reduce a pump's energy consumption by as much as 50%. A variable frequency drive controlling a pump motor that usually runs less than full speed can substantially reduce energy consumption over a motor, which is running at constant speed for the same period.