Buzzing controol unit

[wellusee]

Buzzing bulbs .

I was proud to announce the completion of my ten footer 24v. turbine.  I described how nice it was to hear the control unit buzzing then  see the 10 - 100w - 24v. bulbs come on for dump loading. WRONG! Don't use bulbs I was told they will fail (good advice) use resistors. That buzzing is the FET switches being overworked. So I sent off for the eight Ohmite resistors and built a proper dump load. You may be able to get back to article here .... http://www.fieldlines.com/story/2009/10/23/7492/5750    .... Thing is, the c60 controller is still buzzing but nothing like it was before when dumping. Should there be a slight buzz when it's dumping?

P.

[Opera House]

The reason they buzz is they initially turn on with about 8 times the current. It is surprising that People don't blow out controllers when they try this. The resistance is very non linear.  Having a lot more 120V 100W light bulbs would be a better option (probably about 4 times as many).  Failure rate would be pretty low and there is safety in numbers.

[ghurd]

Some slightly buzz, some do not.  Even in the same production batch.

Even some series (solar PWM) controllers buzz.

A slight buzz is OK.

Good to hear the system is working well!

G-