Hi
Has anyone else had problems using Dagnall or Clairtronic (same company) PCB mount transformers.
I am getting very frustrated replacing burnt out transformers. Firstly the transformers bulge and the plastic case darkens and run noticeably hot. Then, I would assume windings start to short and any fuse supplying the transformer blow. The rate of failure is currently running at around 12 -
15% out of the 500 or so after 18months in use.The transformers we use are the 14VA types which are split primary and secondary, we are running the transformer at around a 50% load factor with occasional peaks for about 10 secs to about 80% rating. When there is a 'burn-out' the blackening only appears in one of the four bobbin segments, sometimes one of the primary and sometimes one of the secondary windings. This seems to point that it is not overload problem as I would expect to see both the primary or secondary windings 'burn' together but so far this has never been the case.
We have approached MGC Electronics who make these transformers in Malta who were of little help and are still holding about 100 of our transformers for 'testing'. We have heard nothing from them for 6 months or more now. We have also approached the original suppliers, Farnell, who say they have had no other complaints and can only follow the findings of the manufacturer.
Our solution has been to swap to a similar unit made by Block from Germany, of exactly the same VA rating, and so far have swapped around 100 over the last year with absolutely no failures whatsoever.
One of my biggest ever mistakes, the day I chose to use Dagnall for our design.
BE WARNED!!!!
Paul Bannister Data Solutions