Dust- and splash-proofed FR-FR700 series drives

With the same high performance as the rest of the power-saving FR-F700 models, the FR-F746 is aimed primarily at the fit-and-forget heating, ventilation and air conditioning sector. The IP54-rated construction provides protection from the ingress of dust and water splashes without the need and additional cost of a protective cubicle. Furthermore, its long service life and minimal maintenance requirements make the drive the excellent for sites and plant rooms where access is difficult.

Designed for building services automation applications and commercial fan and pump control, the FR-F746 series spans the range 0.75–55kW, with frequency output control from 0.5hz up to 400Hz, and incorporates a wide range of control options such as 15 pre-selected speeds, and digital and analogue speed setting. The drive also includes an automatic energy-saving function across the speed range. Crucially, it achieves the most dramatic energy savings in the important low-speed range, and even manages to give optimum savings throughout the acceleration and braking cycles. For example, at a starting frequency of 35Hz, the inverter achieves 57 per cent power saving compared to conventional drives.

In addition, the Optimum Excitation Control (OEC), a Mitsubishi innovation, achieves an average of 10 per cent further saving by ensuring that the optimum flux is delivered to the motor at all times.

Suitable for a three-phase power supply from 380-500V, the FR-F746 is very easy to set-up and configure, using the one-touch digital dial, yet it also incorporates extensive control and data features as standard. The accurate PID speed control meets the technical requirements for a host of applications in the food and beverage, printing and paper, chemicals, textiles and wood industries. The FR-746 variable-speed drive (VSD) also includes a service interval timer to optimise the availability of external equipment, meeting a wide range of customer requirements.

LonWorks communications is increasingly becoming the norm for building services, yet it is just one of the many communications protocols available. The drive also includes communication option cards for Profibus DP, CC-Link, Modbus RTU and DeviceNet fieldbuses as well as having an RS-485 interface as standard.

In offices where noise transmission can be a problem, the drive gives whisper-quiet motor running thanks to its high, adjustable PWM switching frequency. The FR-F746 drive is simple to install, with its own integrated EMC filter (EN 55011A) for RF suppression.

Primarily, the FR-F746 is designed for a host of applications in building services automation, as well as for smoke extraction fans, hot air generation systems, heat pumps, heating and drying cabinets and re-circulating air-heating systems.