From Roundabout To Roller Coaster: Drives And Motors Are Making It Allwork

Mitsubishi squeezes even more energy savings from pump and fan drives Mitsubishi's new FR-F700 series variable speed drive can help save even more energy usage in fan and pump applications, no matter what the load profile, thanks to improved power circuits and powerful processors. Key features include optimum excitation control, which maintains efficient motor operation at constant speed, and optimum torque patterns that ensure instantaneous matching of power delivery to power required. Optimisation in previous products could take several seconds, but with the F700 it is extremely fast, so the drive is always performing at its peak level while consuming the minimum amount of energy. The F700 excitation control is another area of improvement over previous products. In particular, the drive performs significantly better at low speeds, typically saving an extra 12% more energy. This is useful for the many applications of pumps and fans that are rated to respond to rare emergency situations. For the vast majority of their working lives, these devices will operate at low or very low loads, only ramping up to full speed when an alarm condition arises. The F700 also responds very rapidly to changing load profiles. In a mixing application, for example, the torque on the mixer paddles may vary during the mixing process according to the nature of process media; the drive instantly detects these changes and adjusts its settings accordingly in order to maintain peak efficiency. A basic flux vector control is also available for applications requiring high levels of dynamic control. And you can see just how well your new F700 is performing from a glance at the operating panel on its front cover. Parameter selection displays the current power savings in kilowatts, or as a percentage ratio against set criteria. It will also provide the cumulative energy saving in kWh, the actual cost savings (in local currency), and various averages over pre-set time periods - all of which can be downloaded via the drive's integral networking facilities.