Omron's new ac drive offers communication choices
Schaumburg, Ill.- Among product introductions at Omron Electronics LLC 's 4th annual "Technology Connection: A Symposium for Editors" on June 26-27 was a commercial ac inverter (adjustable-speed drive) featuring built-in communication buses that "reduce up-front costs and save user time" in HVAC and variable-torque applications.
Designated 3G3PV, the drive incorporates two software-selectable communication protocols important to this application sector-Metasys, from Johnson Controls, and Apogee, from Siemens. Other networking choices available to the user are DeviceNet (via an option card) and RS-422/RS-485 serial communication. The inverter carries ratings of 0.75-125 hp (0.56-94 kW) at 230 V ac input; and 0.75-500 hp (0.56-375 kW) at 460 V ac supply. It is UL, cUL and CE compliant.
This inverter is designed for commercial applications, which are different from the industrial world, explains Jay Jorczak, inverter business manager at Omron IDM Controls (Houston, Tex.). "We work directly with building engineers, mechanical contractors and maintenance supervisors," he says.
Practical features that appeal to this type of customer are designed into 3G3PV inverter. A removable terminal strip allows the wiring connections to be left intact, in case of drive replacement, or a need to change to a different drive size. In addition, the 3G3PV's faceplate is split and the keypad can be used with access to the terminal strip. Replacement of cooling fans also has been simplified. Operating time of this key drive component is displayed or recorded for the user.
The inverter's high-slip braking feature works without a dynamic braking resistor, leading to reduced cost and space. A built-in dc reactor (for units 22 kW and larger) helps to filter line disturbances and harmonics.
Variable-torque commercial applications for 3G3PV include blowers, fans and pumps. Typical HVAC applications include office buildings, schools, and hotels. Availability of 3G3PV drives is slated for August/September 2002, with an industrial version of the product to follow later.
Control Engineering Daily News Desk
Frank J. Bartos, executive editor