Placing soft start above toroidal transformer

[geminni]

I have a question about placing soft start circuit above toroidal transformer. Is that safe for that circuit?
The soft start circuit has its own small transformer about 2w.

 

[FauxFrench]

"Above" can be at quite a distance from the toroidal transformer. A priori I see no problems as long as insulation distances are respected.
Is your worry insulation, heating, magnetic stray-fields or something else?

 

[scottjoplin]

I've had transformers hum when they were placed too close together

 

[geminni]

The thing is that after some 10 years of usage, the small transformer from soft start exploded. Actually it got blown a little bit, as in picture. So I don't know was that happened because of the big toroidal transformer or what. Just to mention that the main power switch is before everything, so the small transformer is not connected to the mains all the time, there is no standby function.
I have never seen exploded transformer like this 🙂
Everything else in amplifier survived.

 

[FauxFrench]

A transformer "exploded" like that is most likely due to over-heating. For me to see, the stray-field from the big toroidal must be the likely culprit.
I wouldn't have expected such.
What about putting a piece of iron plate (magnetic) in-between the toroid and the soft-start board to provide shielding?

 

[scottjoplin]

I had a similar situation, a normal small laminated core transformer close to a large toroidal, I noticed it hum a lot more than when it was a few inches away and it got hot. In your situation if there is no space I would be tempted to put the soft start in a small external box.