Do these have a practical use for single phase 15/45 service? If so, how would they be wired? Looks like phase & neutral would come in on top but not sure how they're wired out to the circuit from the bottom (3rd poles confusing me). Looks like they offer more protection though????

DZ47LE 1P+N 20A 230V~ 50HZ/60HZ Residual current Circuit breaker | eBay

 

£ 4.5 DZ47LE 1P+N 20A 230V~ 50HZ/60HZ Residual current Circuit breaker | eBay 4 pole and rated current up to 63A. It can protect the line and motor from overload and short circuit It can als...

So far, all the RCBO's I've ordered (assorted Amps but all 30mA unfortunately) are similar to this; DPNL 16A 230V~ 50HZ/60HZ MCB with over current and Leakage protection RCBO | eBay

Simple L/N in & L/N out.

 

$ 5.0 DPNL 16A 230V~ 50HZ/60HZ MCB with over current and Leakage protection RCBO ... It can protect civil electron circuit from over load and short-circuit. Residual current type: AC type. | eBay!

Thanks!

OK, the first one is 1P+N, it does NOT switch the neutral so cannot be used an an incoming breaker.

 

Anyway, if it's not the incomer you simply ignore the leftmost terminal at the bottom (it's blanked off anyway).

Input at the top, live on the left, neutral on the right (marked N).

The live out is the terminal to the left of the one marked N (which is the neutral out).

 

Do please check that whatever you buy does in fact open the neutral if it is supposed to, you wouldn't be the first to be caught out by incorrectly labelled Chinese products.

I bought this one for instance (for a water heater).https://www.aliexpress.com/item/DPNL-1P-N-32A-230V-50HZ-60HZ-Residual-current-Circuit-breaker-with-over-current-protection-RCBO/625670741.html?spm=2114.13010608.0.0.XFYtwh  It also says 1P+N. There's a diagram on it but I'm not familiar with these. Is it ok to use?

I suppose I could do resistance checks with a multi-meter with everything I have so far by opening the breakers to make sure both N & L are truly open. ???

For future purchases should I be looking for 2P maybe?

Thanks!

 

1P+N is fine for internal circuits (although 2P would be better), it's just that 1P+N can't be used as a supply incoming breaker.