MCB Selection

YogendraG

Dear All,

I need help to select MCB for 24 V DC Power supply with 10A current. I want select two MCB DP at input side and output side. I am using 4 no. of Digital Output Card ( 6ES7322-1BL00-0AA0). Is their any calculation to select Proper MCB for the same.For my Control Panel Incomer is 230v for the same I want to select MCB.

Please help to select proper rating of MCB (DP).

Wating for positive reply.

Regards,

Yogendra

HI,

The total load is 24V*10A = 240W.
Hope your power supply is sufficient for all the connectedload.

Let us take a saftey margin of25%.

Hence the total maximummax load on the mains would be 300W.

MCB for protection of the power supply against faults, s/c,

300W / 230V = 1.3A so you need a 2A breaker.

The MCB specified will protect against over current- but not surges etc you need a surge arrestor for that.

suggestion: I'd use a set of 2A quick blow fuse cartridges for this - a MCB would be much too slow. And I don't know if 230V 2A MCB's exist.

Scorpio31

HI,

The total load is 24V*10A = 240W.
Hope your power supply is sufficient for all the connectedload.

Let us take a saftey margin of25%.

Hence the total maximummax load on the mains would be 300W.

MCB for protection of the power supply against faults, s/c,

300W / 230V = 1.3A so you need a 2A breaker.

The MCB specified will protect against over current- but not surges etc you need a surge arrestor for that.

@nkur

Hi there

It doesnt make much of the difference as we are dealing with 1-Ph & P.F. has least significance hence we can can use the same for both type of supply..