Switch 5v using 240v without using a relay

[Scarr]

Hi,

I am looking for a simple solid state circuit or IC to switch 5v-10vDC using 240v mains. everything I'm finding is for switching 240v using a lower voltage.

Steve

 

[ronv]

How much current do you need to switch on the 5 to 10 volts?

 

[NorthGuy]

I am looking for a simple solid state circuit or IC to switch 5v-10vDC using 240v mains. everything I'm finding is for switching 240v using a lower voltage.

You can use something like this.

 

[cowboybob]

Probably best to reduce the mains voltage to more a manageable and safer level (like 12VAC, or even lower) with a "step-down" transformer.

Rectify (and smooth) that ouput and use that to power your solid state (or whatever) device for controlling whatever DC voltage/current level(s) you wish.

 

[MrAl]

Hi Bob,

The opto isolator provides isolation doesnt it? Shouldnt that be good enough?

 

[JimB]

An opto isolator would be my choice.

Obviously something would need to be done about the 50hz, but the way you handle that could influenced by the low voltage being switched.

JimB

 

[cowboybob]

Hi Bob,

The opto isolator provides isolation doesnt it? Shouldnt that be good enough?

Yes, it should.

But to be honest, the more times I read the OPs post, the less sure I am of what he is asking for...

 

[Scarr]

Yes, it should.

But to be honest, the more times I read the OPs post, the less sure I am of what he is asking for...

Sorry if I was not clear, this IC / Circuit is to detect if AC is present, so on one side I have 240v mains and on the other a voltage of 5v that want to be swtiched when the 240v is present (I said 5vdc-10vdc in case it fluctuates a little) so when 240v is present I want the 5vdc switching. hope this makes it clearer.

Steve

P.S. 50mA is the current on the 5v switch side

 

[alec_t]

Here's one possibility, for 230/240V mains. For 110V mains R1 can be omitted.