How to use an Inverter for HVAC noise reduction
In this video Leon Ball, Industrial Technical Account Manager for IDS demonstrates how to use an inverter for HVAC noise reduction.
The demonstration rig Leon uses in this video is our Balloon Rig, which is made up of an inverter, a motor, a fan and trunking with a damper fitted. Which at the start of this demonstration, is almost closed. The balloon gives us a visible indication of the air flow.
First Leon runs the drive in fixed speed, mimicking a normal HVAC installation, so you can hear how loud it is. When Leon starts the rig you can see the motor is running at 96-97% speed, drawing a current of around 0.7 Amps, the noise is such that Leon has to raise his voice to be heard above the noise of the air flow coming from the fan.
Next Leon resets the demonstration, this time he opens the damper wide, to remove the air flow restriction. He runs the inverter in variable speed and will run the motor up slowly and match the balloon’s height on the previous demonstration so we can see the air flow is the same. Already we can hear in the video, the noise has drastically reduced, the current and speed of the motor have also reduced.
A further feature of the ABB inverter is something called “switching frequency” this adjusts the frequency at which the transistors in the drive convert from DC to AC. You can hear quite a high pitched whining noise, Leon changes the parameter of the drive from 4 kHz to 12 kHz. Immediately the noise level is reduced even further and the high pitched noise disappears, yet the air flow remains constant.
To discuss how IDS can utilise noise generated from HVAC systems contact us on 0115 944 1036 or email [email protected]