About my Thoroid transformer...

[john swift]

Any idea what the transformers VA rating is ?

As a toroidal transformer inrush current is very large
I would not be supprised if you need a fuse 3 or 4 times what the VA rating would indicate

if you have a 600VA transformer
you may have to use a HRC 10A mains fuse (HRC = High Rupture Capacity)

and check what type of circuit breaker is supplying the radial circuit your mains socket connected to

for example
a type B breaker trips at 3 to 5 times the full load current operating time 0.04 To 13 Sec

a type C breaker trips at 5 to 10 times the full load current operating time 0.04 To 5 Sec

John

PS

if the transformer is large enough you may have to consider using an inrush current limiter
some examples here -
https://sound-au.com/articles/inrush.htm

PPS
more details of a Soft-Start Circuit
https://sound-au.com/project39.htm