They probably can… but there is a more glaring issue here.
IEC 61008-1 only covers types A and AC.
What you need is IEC 62423, from here.
But then, if it has IEC 61008-1, then it is at least as good as a type-A.
I’d be willing to give the Tongou a chance, but for me the more important test is the impulse test. That’s where cheap stuff usually betray themselves.
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Now you should really explain the difference between type A and B?
Haha. Well, we actually start with type AC. Type AC is the really old original ones, you can still get them, but you really shouldn’t use them in a new install.
- Type AC is typically a simple mechanical breaker, with three windings going around a common core such that the magnetic fields of two of those windings (live and neutral) cancel, and if they don’t, it generates a signal in the third winding which then trips the breaker. This kind of RCD only works properly with sinusoidal leakage current.
- Type A is a little smarter. It can detect DC pulses. So, if you have some sort of DC rectifier somewhere that only leaks half the cycle to earth, this will still detect it and trip. Type A is the minimum you should install in a new installation.
- There are also variants of type-A with some level of nuisance tripping resistance. For example, ABB makes type A-APR, Hager makes type A/HI (high immunity), Gewiss makes type A[IR] (impulse resistant).
- Type F is similar to type A, but works better if the leakage is at higher frequencies than 50Hz. For example, when you have VSDs and other inverter type things that operate at higher frequencies, it might not leak at exactly 50Hz.
- Type B goes further still, and it can detect all leakages, whether they are AC or DC, pulsing or constant.
Edit: So in reference to my Tongou comment, it is sold as a type B RCD, but it only has certification for type-A. People who have tested it reported that it does properly detect 6mA of DC leakage, so it DOES operate like a type-B, and it probably is. But it might not be good enough.
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