Discussion in 'Electronics & Electrics' started by xc351, Dec 5, 2019.
Just wondering what trip curve a standard combo rcd/cb 30mA
In the absence of anything else I'd have assumed they're a C curve.
Aren't you supposedly a sparky? Sounds like you need to read your rulebook again.
Yep I'm a lecky. But do sfa domestic work I'm more happy to play with 275kv than 240stuff. Plus I've never cared before want want a quicker tripping one without down sizing my rcd.
If that's the case get a B curve MCB and put one of those RCD modules on the side. Will cost you more and you'll lose a pole space though...
That's what the rulebook is there for, for reference to the rules, and circuit breaker knowledge is hardly confined to the realms of domestic.
The thermal characteristics of all thermal/magnetic MCBs are essentally the same. Its just the magnetic part that differs. So having a B or a C curve will not necessarily mean it'll trip quicker if your only overloading it slightly...
Why do you need a B curve RCD?
If you need fast acting protection then get a fast acting fuse or similar.
Exactly. The curves are the same, just the magnetic function is further to the right of the curve with C and D curves, so more of the overload function is available to be used.