MCB tripping using relay

[Rajashri.Shevale]

can i trip the mcb by connecting 'live' to the c terminal and 'neutral' to the normally open terminal of the relay. is relay can sustain that much of current?

 

[chuckey]

No you will cause an explosion and write off the relay. What you should do is to replace the MCB with one with a shunt trip (an isolated tripping coil - like a relay coil). You could try and replace the MCB with a RCD. Use your relay to switch in a 30 mA earth leak to trip it.
Frank

 

[kanni1303]

yes you can proceed... there are lot relays with even 30A current rating...

@chuckey: why we can't trip MCB byby activating relay...??? even 30A current rating relay are available any how the relay coil is not going to be connected to the power circuit(Live Circuit) which can be excited separately

this will work are isolator between the embedded circuit and power circuit

 

[FvM]

Major manufacturers offer ST (shunt trip) units to be combined with MCB. Its releasing the MCB by applying an AC voltage to a coil. Alternatively you can use an UR (undervoltage release) unit.

 

[chuckey]

When the relay contacts close there will be a direct short across the mains, so a fault current of kiloamps will flow, before the MCB trips. The relay contacts are rated for 30A maximum current.
Frank

 

[Rajashri.Shevale]

I have omrcn MY2N relay with 12V , 5A ratings. then can i connect it between live and neutral? now i am not going to connect MCB in series with it. I just want to cut power by switching of relay. is it ok if i gonna connect like i said?

 

[FvM]

You didn't specify a load current. Refer to the contact ratings section in relay datsheet.

 

[Rajashri.Shevale]

i want to use this circuitry in domestic purpose, where i think maximum current will be 15A.

 

[kanni1303]

you proceed as it is. there are lot of relays available with ratings of 30A and 250V which will be more enough in your case.
one I searched was 30A Relay