Posted on Friday, 29th July 2011 by Auw Jimmy
Last upgrade, the switches. Basically, in most tube application, we will use two switches. The first is the main switch which will control the main AC voltage to supply the main transformer. The second one is the one which commonly called as stand-by switch. This will control the High Voltage (either cut in AC – before rectification or DC – after rectification) supply to power up the tube.
The first switch is quite easy to get, as this is common voltage (either 110 VAC or 220 VAC). But the second one is not too easy, since we will deal with voltage more than 220 VAC (usually 300-500 VAC/VDC). Most people will use standard 220 VAC rated switch, which is actually quite safe, since this second switch only run <200 mA current (most 220 VAC switch is rated 5 A or more).
But as this is the ultimate project, of course we will not use such shortcut approach. After some searching around, my choice hits to the Leviton 30A – 600 VAC rated switch. This double poles switch has silver-alloy contacts and designed for fast-make/slow-break. This is really what I’m looking for from a High Voltage switch. With 600 VAC rating, I think I can sleep very well when use this one on 350 VAC secondary.