Hardwired Balanced mains transformer install

GazjamGazjam
edited June 2013 in DIY
Tried posting my image heavy build log for this, but couldnt get the images to embed properly..

Hope its ok to link to the AOS forum for you guys to read it.
Discuss it here though!

http://theartofsound.net/forum/showthread.php?26471-Balanced-Mains-Transformer-WOW!-Hardwired-Installation-log-(Pic-Heavy!)

Hopefully its useful and food for thought for some.
Best upgrade in my system - dont spend loadsa money on your system until you have the mains sorted!!

Comments

  • sovereignsovereign
    I've been waiting for this for ages, lovely!

  • AlanAlan
    It does look excellent, doesn't it? I am quite keen myself, I hope Col sees this, and Paul as well.

    Gaz, does the airlink buzz much?
  • GazjamGazjam
    edited June 2013
    Hey Sov,

    You know what, it hardly buzzes at all.
    You have to literally put your ear close up against the casework to hear a VERY low hum.
    On switch on there's an initial pulse, but that goes away after 10 secs or so.
    I leave it permenantly switched on so not an issue.

    In my install its not a problem anyway, as the transformer is set up in the next room, the output cable fed through a hole in the adjoining wall, feeding the junction box behind my hifi rack.

    One thing Im noticing is that the sound has been changing over time?
    The bass has vanished this morning but a couple of days ago it was vibrating the sofa!

    More improvements to come I think.

  • AlanAlan
    I noticed this, when I modified my mac and also, to a lesser extent, when I re-capped my pre. Gross changes, all over the place for about a week or so.

    This balanced malarkey looks very do-able, its been on my radar since Jim K recommended it 2 years ago.
  • sovereignsovereign
    Hey Sov,

    You know what, it hardly buzzes at all.
    You have to literally put your ear close up against the casework to hear a VERY low hum.
    On switch on there's an initial pulse, but that goes away after 10 secs or so.
    I leave it permenantly switched on so not an issue.

    In my install its not a problem anyway, as the transformer is set up in the next room, the output cable fed through a hole in the adjoining wall, feeding the junction box behind my hifi rack.

    One thing Im noticing is that the sound has been changing over time?
    The bass has vanished this morning but a couple of days ago it was vibrating the sofa!

    More improvements to come I think.

    I'm glad it doesn't hum mate, mine does a bit, the more load it has on it the more it hums, I may put some swidgy feet under it
  • uglymusicuglymusic
    That does look interesting.

    Maybe I should buy a soldering iron and start making some stuff.
  • GazjamGazjam
    edited June 2013
    Sov,
    is it Jerry's 1.5 KVA unit you have?

    I wonder if a higher rated unit like mine doesn;t buzz becasue its got more "reserve" capacity?
    Its the plug in unit?

    If you want to go "full bhuna" on it I'd recommend going hard wired...I've faffed about with cables, plugs and even different types of plated fuses for years, and taking all those variables out of circuit really has improved the sound (as well as my audiophile OCD! :))
  • sovereignsovereign
    Yes it is 1.5Kva, It's hard wired as, like you, I see little point in plugs etc.
    I used to have a 3.4Kva BPS a few years ago and that hummed even more!
  • sovereignsovereign
    My Question is is your set up legal, I don't mean safe.
  • PACPAC
    Nice project Gaz...one thing rings alarm bells though.

    You mention taking fuses out of the equation?  They're there to protect the cables from catching fire and burning the house down in the event of a fault current developing with your kit.  There should be a fuse between wiring in the wall and the box somewhere I think, otherwise I'd doubt it complies with any current regs...be careful as it will affect your insurance (ie they most certainly will not pay out in the event your house catches fire).  Be safe!
  • sovereignsovereign
    Nice project Gaz...one thing rings alarm bells though.

    You mention taking fuses out of the equation?  They're there to protect the cables from catching fire and burning the house down in the event of a fault current developing with your kit.  There should be a fuse between wiring in the wall and the box somewhere I think, otherwise I'd doubt it complies with any current regs...be careful as it will affect your insurance (ie they most certainly will not pay out in the event your house catches fire).  Be safe!
    I wonder if you need a fuse or if you could get away with a RCD?  An RCD will trip within a fraction of a second where as a fuse will burn a lot slower, but insurance companies and rule book junkies 
  • PACPAC
    According to BS1362 you need to fit a 3A fuse to protect the cable of the appliance draws up to 700W and a 13A fuse if it is rated above 700W.  Part P of the Building Regulations stipulates that any electrical work undertaken (involving hard wiring) must be undertaken by a "competent person" and furthermore, some aspects of the work may require building regs approval.   I may be wrong, but at present I think that irrespective of what RCD devices are fitted at the consumer board, fused plugs need to be fitted at the wall socket, or the socket itself should be of the fused variety such as the ones commonly used for spurs for cookers and electric showers.
  • GazjamGazjam
    edited June 2013
    Part P doesnt apply to Scotland guys.

    theres 3 fuse "systems" in the chain:

    Consumer Unit RCBO
    Balanaced transformer has MCB protection on input terminals and RCBO protection on the outputs.
    Each bit of kit is internally fused.

    The only sticking point I could see when i was looking into it was that as I was hardwiring into the ringmain and removing a switched double socket, I was technically removing the ability to  kill the supply locally, which is a requirement oop North.

    Its fine though, the Balanced mains has SWITCHABLE MCB and RCBO protection, so it acts as a local switch at that point in the ring main.
    So technically the balanced mains acts as the "socket", and it has suitable RCBO/MCB protection, which is what you get with hardwired cookers etc.

    Thats what my spark advised me, all ok he said.

    theres no chance any current can either leak to earth or set fire to the cable, as the CU would trip first, and if for some reason it didn;t the breakers on the Balanced mains would.
    Last line of defence is the internal fuses in rach bit of kit.

    Also theres no plugs in the setup, so BS1362 doesn't apply ;)
  • sovereignsovereign
    I'm about to run a separate supply from the main tails coming into my house so all this is very topical for me, the only other consideration I have is that I also run a AG1500 along side my BPS.
    My install will very much be along the lines of Roy K Riches but I have to stick to the law as much as I don'y always want to.
    The electrician who is carrying out the work is one of the chaps I use in my business and he most certainly knows his stuff.  
    I just want the least complicated, lowest impedance supply I can. 
  • GazjamGazjam
    Sounds a good way to do it Sov.

    Roy has a very comprihensive set of notes relating to every aspect of this, but you probably have all that already.
    I'd have went the same route you are talking about, but cant do that in the property Im in, so had to go for the next best thing.

    Keep us up to date how your getting on, I know theres a few forums all interested in this stuff!
  • PACPAC
    Sounds like you've thought it through Gaz and have plenty of redundancy built in plus your sparky's given it a clean bill of health which is reassuring for you.  Didn't realise you had a switchable MCB/RCBO protection, so all sounds safe and sound.  Regs are applied differently oop North which I always find odd, because the Electrical Regs are derived from the European standards (Directives). As you rightly point out, Part P doesn't apply in Scotty Land
  • figlet108figlet108
    So who's this Roy Riches chap and what notes does he have on this? I'll be doing similar things to Sov and Gaz within the next few weeks...
  • sovereignsovereign
    Roy K Riches is a man who committed many many years of his life into researching the effects of mains on hifi, a bit of an authority on the subject.
    He used to be on PFM a lot but not for quite some time now, look up his name or RKR on pink fish.
    He has written reams on the subject which I can email to you if you want   
  • GazjamGazjam
    Yup, Roy's the man.

    Looking fwd James to your findings with the BPS and the regen unit.
  • figlet108figlet108
    Sorry James, I very rudely didn't thank you for that reply - I'll do some research on Roy before I start - off to visit my folks in Greece so I'll have some time to WILF him up...
  • AlanAlan
    Have a great time with the family Jason.

    Roy is well worth emailing yourself - he'll send you about three maxed out emails of references and instructions, which are worth a look. He is most generous with his time and experience. I can pm his email address if you like.
  • figlet108figlet108
    edited July 2013
    Would love that - thanks Alan.

    BTW, very happy that the TSS Alan (sounds like a battleship) went to a VERY good home.


  • AlanAlan
    Me too. I would have felt bad if Justin got stuck with it.

    I'll get that email address to you shortly.
  • sovereignsovereign
    I have the BIG install happening on Tuesday!
    Having a separate power installation from the main tails of the house to my hifi.  With the Ag1500 in place and the BPS I have no idea if it will make any difference, but I can only try. 
  • uglymusicuglymusic
    Good luck!
  • AlanAlan
    Very exciting James - we want updates and pics!

    Good luck.
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