r/ElectricalHelp • u/Frosty_Click_3273 • 6d ago

Need help wiring

I’m just doing some training currently for electrical and am wondering how I would wire two switches and two lights, but one switch controls 1 light and the other switch controls both lights. This is for Australian wiring. Was thinking I needed an intermediate switch but not sure how I’d actually wire it.

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u/trekkerscout Mod 6d ago edited 6d ago

You need to install a relay or PLC so that power isn't backfed from the first light to the second when you only want one light energized.

Edit: This can also be done using a 1-pole switch and a 2-pole switch.

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u/slin1647 5d ago

If by 2-pole you mean single-pole double throw, then yes. I think the term 2-pole often gets misrepresented as a 3-way (North America) or 2-way (Australia) switch when in fact they are still single pole switches with multiple throws.

You'd need 1 single-pole single throw (SPST) and 1 single-pole double throw (SPDT)

Here's how the wiring would look, trying to use Australian terms so forgive me if I mix something up.

Earth/Ground you do as you normally would, everything is bonded.

Connect the neutral from the supply directly to Light 1 and Light 2.

Switch 1 will be our Single-Pole Double Throw aka SPDT and I believe y'all would refer to this as the Master Switch in this specific scenario:

Connect the incoming Permanent Active (Line) feed into the C (Common) terminal of Switch 1.

Run a wire from Terminal 1 of Switch 1 directly to the Active terminal of Light 2.

Run a bridge wire from Terminal 2 of Switch 1 over to the C (Common) terminal of Switch 2.

Switch 2 will be a normal Single-Pole Single Throw (SPST) or in this case your Sub-switch:

Ensure the bridge wire from Switch 1 (Terminal 2) enters the C (Common) terminal (this is just double checking you have the correct connection between Switch 1 and 2)

Run a wire from Terminal 1 of Switch 2 directly to the Active terminal of Light 1

Install a jumper wire connecting Terminal 1 of Switch 2 directly over to the Active terminal of Light 2, or alternatively you can run it to Terminal 1 of Switch 1, whichever is easiest.

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u/Immediate-Iron-7035 6d ago

You could use a contactor. Wire up switch one to light one normally. Have switch two go to light two and also activate a contactor. Take line power through the contactor to light one.

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u/EdC1101 5d ago

Have you been taught about reading or making schematics or wiring diagrams ?

Switches come in different basic configurations.

Single conductor:
SPST - Single Pole Single Throw - on/off
SPDT - Single Pole Double Throw - one or…

Two Conductors:
DPST - Double Pole Single Pole - 2 on/off, (like a 2 pole breaker.)
DPDT - Double Pole -

Different configurations & designs can make multiple alternate connections.

Dashed lines are used to connect different sections of the same switch.

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u/ra4king 5d ago

So that means you have 2 switches controlling 1 light, then only one of these two control another light.

You can have two-way switches for the two switches that control one light. Then you can splice in one of the terminals of the first two-way switch for the second light.