Inverter drives | eight more lesser known facts

Drives have been a key technology for industrial engineers for many years but Matt Handley of Mitsubishi Electric thinks they can be underappreciated. Here he highlights his second eight from a list of twenty five of the interesting facts about them.

9. In energy saving applications returns on investment on the purchase of a drive can be as quick as 6-24 months. The expected life of a drive is over 10 years, so substantial lifetime cost savings are achievable.

10. As a carbon reducing technology, Enhanced Capital Allowances are available on drives. This effectively reduces their purchase price, speeding up the return on investment. For details see http://www.carbontrust.com/

11. Drives can work in a standalone mode but also have high level communications capabilities, so are suitable for use in automated systems, computer integrated manufacturing, machine-to-machine communications, the Internet of Things and Industry 4.0 installations.

12. The high speed lifts used to service the upper floors of skyscrapers use finely tuned drives to accelerate the cars up to a great speed, then slow them down and park them precisely at floor level, while providing passengers with an incredibly smooth ride. When the CTF Financial Centre in Guangzhou, China, is opened next year the lifts will ascend at 20m/sec, three times the speed of those in New York’s Empire State Building. Originally skyscrapers were constrained to about seven storeys because the steam driven lifts were so slow.

13. A drive can temporarily run a motor at above its rated power. This means motors can be sized for normal duties, rather than having to be oversized to cope with possible but rare overloads. This can lead to significant energy savings. Up to 95% of motors installed today may be oversized.

14. Total global energy saving potential of drives in use today is reckoned to be 500 Terawatt hours.

15. The power circuits in a large drive generate considerable amounts of heat as a by product. In the past this tended to be simply vented to atmosphere but increasingly it is being captured via a heat exchanger and put to work for preheating water for hand washing and other uses.

16. The biggest drive in the world is probably one used in a giant wind tunnel built by NASA to test space vehicles and capable of running at transonic speeds.

Go here for the first eight of Matt’s inverter drive facts

Go to 999 Inverters for Mitsubishi Electric’s complete AC variable speed inverter drive line-up