I'd like to use two rocker switches, each is single pole and including a light bulb on the inside (230VAC) to control the powering the system.

I'd like to connect both of them to the transformer with single primary winding(230VAC) and double secondary windings (each rated as 26V), but here's the trick: The RED rocker switch is the "head" of the circuit: if the red one is turned off, then nothing should be working (neither +26V neither -26V line). But, if I turn on the RED switch, the +26V line must be turned on, while I have an option to turn on the -26V line with the GREEN switch or not. Only turning on GREEN switch while RED is turned off should result into both circuits being turned off.

Here's a chart I've written, how should schematics work.

RED | GREEN | +26V | -26V
 0  |   0   |   0  |   0
 1  |   0   |   1  |   0
 0  |   1   |   0  |   0
 1  |   1   |   1  |   1

And here's the schematics.

enter image description here

  • 1
    \$\begingroup\$ your logic chart needs only three lines ..... when the red switch is off, then the green switch should be a "don't care" state designated as X \$\endgroup\$
    – jsotola
    Jan 13 '19 at 19:31
  • \$\begingroup\$ Why not just use different switches? \$\endgroup\$ Aug 15 at 23:40

I would put the red switch in the same wire as the fuse - that should be the Live wire. For AC wiring, you should always switch the "hot"/Live wire, not the Neutral.

I would put the -26V switch in the -26V wire, rather than in the Ground. Either way would work, but it makes more sense to me to switch the "hot" wire. The lamp lead for the -26V switch should go to GND, but if it is desigend for 230V, it probably won't light with only 26 volts.

  • \$\begingroup\$ Thanks for the comments, they will come in handy and will change the schematics. Yes, that's the actualy problem: it won't turn on just on 26 volts. Therefore I'm searching for the alternative wiring, while keeping same components. \$\endgroup\$
    – Jakey
    Jan 13 '19 at 19:58
  • \$\begingroup\$ You could try taking the lamp lead to +26V - but it depends on the type of lamp in the switch. If neon, you'd need more than 80 volts or so to light it. \$\endgroup\$ Jan 13 '19 at 21:04
  • \$\begingroup\$ It's not neon. It's probably regular lightbulb inside. It's most common rocker switch that can be commercially hound. \$\endgroup\$
    – Jakey
    Jan 13 '19 at 21:22
  • \$\begingroup\$ if it's a LED in there it will quite a lot work to light it. if it's a neon you can make the connection shown \$\endgroup\$
    – Jasen
    Jan 13 '19 at 21:27

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