Coherent RTZ GROUNDING BOX

[Bigman80]

Thanks for that link Al. In fact I hoped you would respond, knowing you both use a BMU in your system and work in the electrical distribution business.

Actually I had seen that item before, but could not remember where. I have now bookmarked it.

Clearly, any competently designed BMU needs to have a circuit breaker fitted to both legs of the secondary winding, and for the two breakers to be mechanically linked, so if one trips the other is also disconnected.

Mine is a DIY BMU and has MCBs in both legs. It's also substantially earthed and complies fully with the latest regs.

With two small kids in the house, it's a must that everything is safe.

[blackmetalboon]

Mine is a DIY BMU and has MCBs in both legs. It's also substantially earthed and complies fully with the latest regs.

With two small kids in the house, it's a must that everything is safe.

Are you sure the part I have highlighted is correct? For optimum safety it should be a double pole RCD on the secondary supply of the BMU.

[Bigman80]

Are you sure the part I have highlighted is correct? For optimum safety it should be a double pole RCD on the secondary supply of the BMU.

Yes it's a double pole RCD on the secondary.


Actually, I can't remember if it's a MCB or RCD.

I'll have to have a look

[hifinutt]

I don't have a balanced mains unit and wouldn't mind seeing how this unit sounds with the fb monoblocks sometime

[Bigman80]

I don't have a balanced mains unit and wouldn't mind seeing how this unit sounds with the fb monoblocks sometime

Matey, if you come and get me and drop me off home after, I'm more than happy to bring it. That said, the conventional wisdom is not to plug a power amp into them.

No idea why. It could also be Bullshit

[Marco]

Interesting review on the grounding box, Oliver.

For me, your findings aren't surprising, because by the very nature of how these things are claimed to work, they're likely to be system dependent, due to how the partnering equipment itself is designed (in reference to grounding) and the operating environment where the box is being tested - and if significant differences occur there, then you're liable to get quite different results, from system to system, as was the case in yours and Alan's.

It's a warning though, that these boxes, much like anything else in hi-fi (BMUs, too) can *never* automatically be seen as a 'magic bullet'!

Marco.

[Joe]

It is interesting but I certainly don't see it as a bubble that will burst as you put it.

I guess it depends on whether it injects air or removes it.

[Ali Tait]

Thanks for that link Al. In fact I hoped you would respond, knowing you both use a BMU in your system and work in the electrical distribution business.

Actually I had seen that item before, but could not remember where. I have now bookmarked it.

Clearly, any competently designed BMU needs to have a circuit breaker fitted to both legs of the secondary winding, and for the two breakers to be mechanically linked, so if one trips the other is also disconnected.

Yes indeed, I built mine with a double pole RCBO on the secondary and double pole MCB on the primary.

[Bigman80]

Yes indeed, I built mine with a double pole RCBO on the secondary and double pole MCB on the primary.

Ah! This rings a bell. I'll look into this tomorrow.

[Bigman80]

Interesting review on the grounding box, Oliver.

For me, your findings aren't surprising, because by the very nature of how these things are claimed to work, they're likely to be system dependent, due to how the partnering equipment itself is designed (in reference to grounding) and the operating environment where the box is being tested - and if significant differences occur there, then you're liable to get quite different results, from system to system, as was the case in yours and Alan's.

It's a warning though, that these boxes, much like anything else in hi-fi (BMUs, too) can *never* automatically be seen as a 'magic bullet'!

Marco.

Rarely is there a one size fits all solution. This highlighted that perfectly.