I am working on a clapper (original, i know) and need to pass 230 V AC, to power a light bulb. For this i am thinking a relay is the right choice, but i am struggling to understand the specifications.

For now i am in possession of this relay:


It might be a poor choice for mains voltage, but lets take it as an example to understand the specs.

It states a max load of:

0.5 A at 125 VAC

2 A at 30 VDC

And a max switching voltage and current:

125 VAC

2 A

What is the difference between load and switching voltage/current?

And if i need to power a 60 W light bulb, with 230 V, will i just need a relay that can handle 230 V and ~0,3 A at max load, and as switching?


The max load is continuous while the max switching is, well, switching. However, it is misleading, Max 2A switching is actually at 30Vdc. You need to look at the graphs in the spec for real numbers.

enter image description here

However, this device is NOT large enough to switch a standard 230V 60W incandescent light bulb. Not only by voltage but also by current.

It may take only .3A once hot, but when starting form cold the current will be A LOT more than that, ~15 times.

Closer to 4A in fact. So you need one that switches 5A @ 240V.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.