NEWS
How does the wind affect your ventilation? Good ventilation systems and temperature control on farms is paramount in ensuring the health of livestock. “Living in Victoria, I know how the northerly wind can blow hot and hard during the summer months and therefore the combination of heat and wind is a double hit for most farmers,” said Simon Bradwell, Managing Director of ebmpapst A&NZ. “Traditional ventilation systems typically consist of an AC-capacitor motor or an AC three phase motor if the power is higher,” he said. “Typically a small motor and a large diameter fan are used and will, at full speed, have a low torque. As evidenced by many users, at a wind pressure of 10-30 Pa on the building the fan will not rotate as fast as its nominal speed. “If then the ventilation system is controlled to a lower set point by the voltage controller, the torque curve is not linear and it will become increasingly more sensitive to wind and wind gusts. “This means that the ventilation of the farm is note adequate, and not in control,” Mr Bradwell said. “As shown in Figure 2, EC-fans have full torque from approximately 8% and the torque/rpm relationship is linear. This means that the fans will not slow down due to wind which again means that we are able to drive the fan at the exact needed set point in full control.
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Figure 1: The torque speed characteristics of many Single phase AC motors “This saves energy, ensures that the system is in control, and the environment is correct for the animals. About ebm-papst “The ebm-papst Group is the world’s leading manufacturers of fans and motors and is a pioneer and pacesetter for ultra-efficient EC technology,” said Mr Bradwell. “ebm-papst fans and motors are represented in many industries, including ventilation, air-conditioning and refrigeration technology, household appliances, heating engineering, in IT/telecommunications, in medical technology and in applications in automotive and commercial vehicles engineering. ebm-papst EC motor technology, and the market leader’s engineering and logistics expertise will add value to your business.” For more information go to www.ebmpapst.com.au
Figure 2: The torque speed characteristics of many EC and DC motors.