What is the purpose of a step-start circuit in a high-voltage power supply?
To provide a dual-voltage output for reduced power applications
To compensate for variations of the incoming line voltage
To prevent arcing across the input power switch or relay contacts
To allow the filter capacitors to charge gradually✓الإجابة الصحيحة
الشرح
Uncharged filter capacitors look like a short circuit at the instant power is applied. A step-start circuit inserts a resistance in series for a fraction of a second and then shorts it out, letting the capacitors charge gradually and limiting the inrush surge.