Thermistor location for psu

Hi Thanks for reading. I have a large transformer and want to use a soft start as the mains keeps tripping everytime i plug the transformer in.
In the pass labs f5 amp they use a single thermistor in between the two primary windings. The transformer i have is encapsulated so cannot access the windings. I have the two mains cable live and neutral sticking out of the encapsulation, and four cables for the two secondary windings
Where can i put the thermistor, and which thermistor would you use for british ac 240 volts, something rugged.
The two secondaries are 15 amps each
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Simple solution, buy a soft start module. If done right it helps you to keep mains voltage and secondary voltages apart. There are some that even have a very small transformer for the cirquit, those can be triggered by different kinds of switches. Maybe look at ebay.

The low part count version is a resistor, like 5 Ohm 20 Watt and a relais that bridges the resistor, just a fraction of a second later, driven by the secondary DC voltage. The not so nice thing is to have the mains voltage near to the secondary's.

Lke this|tkp:Bk9SR4zSje_dYQ