Inrush current ! what inrush current ?

As per picture, torroidal transformers are well known for their superior efficiency compared to the laminated type, they are typically very efficient from 0% loaded all the way to 100% loaded, this is great if you leave a torroid in circuit but when you switch them on and off they have an enormous inrush current issue. In days gone by we would and can still very successfully use Thyristors to soak up the inrush but they need a cool down period in between switching. As you can see in the picture, we are turning on and off a torroid with a secondary current of circa 70 amps (orange outline) and a primary of circa 7 amps, we are energising and de-energising every minute constantly without inrush current (blue outline)

Just another clever development by matt: Ltd, caring about your world :)