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Mains IEC Connectors, I never realised !!

thommy said:
All this stuff sometimes makes a huge difference if you have a good amp and speakers. The only people who think it can't have a very rudimentary working model of what the universe is. I just hammered a 4ft copper rod into my garden to connect as a ground to my DIY mains conditioner. Can hear the difference there too. The resistance of the mains supply to the transformers in any equipment will affect how fast changes in power demand can be met. Dynamics rely on being able to suddenly grab more power and so bigger cables that conduct better and have a lower overall ESR (equivalent series resistance) are going to allow a better performance. Each of my mono amps has a 1000W isolation transformer feeding them which basically gives a reservoir of power to allow faster response to changes in dynamics. My isolation / conditioner box is an essential part of why my system sounds so good.
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How is your hoise wiring earthed? If you are pme and in the UK you will need to bond that earth back to mains
 
Beobloke said:
But the fuse is NOT a bottleneck, therefore neither is the cable. The difference in resistance between a 13A Cooper Bussmann fuse and a 3A one is a smidge over 39milliOhms which will have absolutely no effect on the power transfer of 230Vac or the sound.

In fact, if 39mOhms really does have an adverse effect on a PSU then it’s horrendously badly designed!

As to your pieces of 1mm wire where a fuse should be - so you’ve left the cable with no protection? More importantly, does your house insurance provider know?
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The fuse is there to blow in case live shorts to neutral somehow and tons of current goes to ground via the neutral-ground tie, right?

What else breaks the connection when current starts flowing from live to neutral?

An RCCB, which I already said is in the box. The cable is just an extension of the ring.

The whole point of this discussion is that these things DO have an effect so there must be something wrong with your working model of what is happening in the electrical system.
 
S-Man said:
Spot on!
I also don’t like Schurter IECs. I have no idea how they got their reputation.

Taking things a step further I have wondered if all my boxes should be joined together with braided earth straps, perhaps using the preamp (active crossover in my case) as the star point?
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Star earth is in general a really good way to make an antenna to receive rfi
 
martin clark said:
What you have described, definitely is. You've tied whatever the incoming Earth route your Supplier has provided, to a freehand addition of your supplier.
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I never said anything about linking the copper rod that I put in to the house wiring. In the box are 3 transformers which galvanically isolate the hifi from the mains. Transformers have two wires so no need for a 3rd wire in the cable except to ground the chassis for safety. If i connected the grounds from the gear to the house wiring that would negate the isolation. Ground wires aren't unidirectional, they are like an open window that can let electrical demons out, but also let them in. i dont like electrical demons in my stereo but I also dont want to die so I created another demon-free link to ground to ensire the whole system is galvanically isolated and therefore demon free.
 
Beobloke said:
But the fuse is NOT a bottleneck, therefore neither is the cable. The difference in resistance between a 13A Cooper Bussmann fuse and a 3A one is a smidge over 39milliOhms which will have absolutely no effect on the power transfer of 230Vac or the sound.

In fact, if 39mOhms really does have an adverse effect on a PSU then it’s horrendously badly designed!

As to your pieces of 1mm wire where a fuse should be - so you’ve left the cable with no protection? More importantly, does your house insurance provider know?
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Cables dont need to be protected but theres a 100A RCCB in the box the cable connects to in case one of the transformers has a meltdown.
 
thommy said:
I never said anything about linking the copper rod that I put in to the house wiring. In the box are 3 transformers which galvanically isolate the hifi from the mains. Transformers have two wires so no need for a 3rd wire in the cable except to ground the chassis for safety. If i connected the grounds from the gear to the house wiring that would negate the isolation. Ground wires aren't unidirectional, they are like an open window that can let electrical demons out, but also let them in. i dont like electrical demons in my stereo but I also dont want to die so I created another demon-free link to ground to ensire the whole system is galvanically isolated and therefore demon free.
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You could have just bought some shaver sockets…
 
martin clark said:
@S-Man

Erm - doesn't that just risk creating, as much as resolving, stray earth-bond currents..? There is a difference between inter-chassis potential, earth leakage, and CM shite from some stray PSU. So at least three different strands of corruption..?!

I'd rather define where such can flow.

Anyway - I had that same thought years ago, and set-about measuring differences with a DVM - since even a cheap dvm has input impedance in the 10^8ohm range, measuring interchassis-voltages soon shows if there's an issue. Bought better DVM..

For my own pile - I'm at limit of resolution , 1uV +/- a count or two (or whatever it is in the manual), and thats just.so.far into the long grass - its beyond-irrelevant for audio. That with a simple DIY hydra, 7 boxes (all linear supplies); and the ESLs powered (pair of mains leads, no mains earth connection on Quads) via another plugtop into the other socket on a standard UK switched dual-outlet faceplate.

Then again - the ESLs by design , are transformer -isolated from the rest of the sistem, in two senses. Or , maybe I'm just lucky.
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That’s what I ended up with – a DIY Hydra.
 
thommy said:
The whole point of this discussion is that these things DO have an effect so there must be something wrong with your working model of what is happening in the electrical system.
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J.C. Maxwell & O. Heaviside readily disagree...

thommy said:
Probably like other houses. Bonding the new earth to mains would defeat the point.
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Also - defeats the most basic defined Safety requirements.
ffs
 
thommy said:
The fuse is there to blow in case live shorts to neutral somehow and tons of current goes to ground via the neutral-ground tie, right?

What else breaks the connection when current starts flowing from live to neutral?

An RCCB, which I already said is in the box. The cable is just an extension of the ring.

The whole point of this discussion is that these things DO have an effect so there must be something wrong with your working model of what is happening in the electrical system.
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An RCCB only protects what comes AFTER it, not the input supply to it, which is coming down your unprotected cable!
 
thommy said:
Why does a cable need to be protected? Whats it going to do apart from potentially strangle someone?
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Jeez.

To re-iterate things long-posted by several people, many times here before:

..because the UK uses 240Vac mains, and a Class B 32A breaker on the ring.
You can, actually - you bloody-should - look-up the time: fault current curves for breakers...

So: a typical class B breaker doesn't get out of bed below 2 x overload for ~60s, so now you have potential 64A - likely rather more - as a sustained, prospective-fault-current, and that through some cheapo flex cable - is >> 24Kw, or if you like >32+HP dissipated as heat in a 'flex' - and that means fire , right-damn-quick.

Christ.
 
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