Re: LF: How can you tell if a Class D amp output transformer is starting to saturate?

[Chris Wilson <dead.fets@gmail.com>]

Hello Andy,

Sorry  for  the  late reply, work intervened and the grass grew to the
level  I  had  promised my wife it would never again get to, so I have
been  limping  the  old  ride on around praying it would not throw its
toys from its pram again in protest at the strain ;) I am assimilating
the  maths,  slowly, very slowly. is there any visual way to see if an
output  transformer  is saturating? I wound a few loose turns around a
5kV  transformer  to  look  at  the  patterns when running it near its
input  voltage  and  output  current  limit,  some years ago. No maths
involved,  which  is  of great comfort to me. Thanks for your detailed
reply. 

Thursday, May 3, 2018, 3:00:36 PM, you wrote:

> By measuring the voltage across the winding using a scope, then
> seeing what Bmax is using teh equation


> Vrms = 4.44.F.N.A.B


> F Hz     N turns   A core cross-sectional area in metres^2    B tesla


> If B works out higher than about 0.1 for a ferrite core, then you are 
> approaching saturation

> Andy
> www.g4jnt.com





-- 
Best regards,
 Chris                            mailto:dead.fets@gmail.com