Cooling Fans

[Shiner 2]

I have an application where a desired temperature range is required. The thought of the engineer is to have a VFD running the fans but I am limited on what I have found that applies. I have single phase 120VAC drives and fans, which present no problems. The trick comes in that the fans need to have Ionization built in for purposes of air quality and the drives will negatively affect their performance. Any products or ideas would be greatly appreciated.

[JRoss 84]

How tight is the temperature range? Could you do it with a two or three speed fan?

[Shiner 2]

We had thought of that but it is a tight range so switching between two or three speeds could just end up causing an oscillation in the process.

[JRoss 84]

What about using an air conditioner with ionizing fans?

[Shiner 2]

not a bad idea either unfortunately we are constrained on size because this is part of a product line. We are using the moving air to regulate some elements that have a peak output at less than normal operating temperature. The goal is to try to reduce the temp enough to increase the output and speed up the line's capability at low cost and size.

[BobB 58]

Have you tried using a loop powered RTD transmitter into the VSD? I have used this in the past to drive the VSD up and down in a tunnel type power station underground - Military.

[JRoss 84]

Yes, a lot of vfds have a PID function available. Good suggestion!