Hottub mcb selection

[Dvyj123]

The hottub is 8.1kw so will be 35A max output , I’m going to put it on 6mm 3core swa to an isolator then to the hottub. Would a 40a b type be sufficient for this ? Or would it be better to put it on a 40a c type mcb? Thanks

 

[nicebutdim]

What would be your reasoning for considering use of type c?

 

[Dvyj123]

What would be your reasoning for considering use of type c?

I’ve heard of some hot tubs having a spike when starting up and people thatve put them on a type c aswell as b just wanted to confirm what would be better

 

[nicebutdim]

I’ve heard of some hot tubs having a spike when starting up and people thatve put them on a type c aswell as b just wanted to confirm what would be better

Does the manufacturer specify a particular protective device and will ADS be met with type c?

I'm asking questions as your profile indicates trainee status and OP provides insufficient information to provide an empirical answer.

 

[Avo Mk8]

While the 'hot' bit of a hot-tub load is resistive, there can be fairly beefy pumps for water jets and bubble jets, so I can understand there being a significant transient in load current if pumps are turned on while the heating element is running!
Edit: But as above, that doesn't mean bodging protection to avoid a problem!

 

[Dvyj123]

Does the manufacturer specify a particular protective device and will ADS be met with type c?

I'm asking questions as your profile indicates trainee status and OP provides insufficient information to provide an empirical answer.

It is quite an old tub so doesn’t have the manufacturer instructions and cannot find out what it is, the only thing I could find on it is the max output that was 8.1ka