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Testing of radial circuit,which feed an ring final circuit

Discussion in 'Electrics UK' started by rockenroll, 20 May 2008.

  1. rockenroll

    rockenroll

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    So :D , you have on CCU 32 Amps type B MCB which feed a 3 phase+n isolator BS 88 fuse 32Amps, thru 3x4mm single core conductors(phase,neutral,earth)...
    From isolator is connected a ring final circuit thru 2.5mm conductors
    You must test this circuit and complet the test of schedule results
    :?:
    Any remarks :?: :?: :?:
     
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  3. holmslaw

    holmslaw

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  4. Spark123

    Spark123

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    You could treat the 3p+n isolator as a separate CU.
     
  5. rockenroll

    rockenroll

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    The CCU is TP+N,main switch is 100Amps BS 60947, untill here everything is ok :D ,on CCU u have 4 circuits,one of them is the 32 Amps type B MCB which feed a 3 phase+n isolator BS 88 fuse 32Amps, thru 3x4mm single core conductors,(phase,neutral,earth),enclosed in PVC trunking, where the phase is connected on L1,neutral to neutral bar,earth to neutral earth,(L2,L3-unused),
    From TP+N isolator is connected a ring final circuit thru 2.5mm conductors as follow, the 2c2.5mm for phase ring final is connected to L1, 2c2.5mm for neutral is connected neutral bar and 2c2.5mm for earth is connected earth bar
    You must test this circuit and complet the test of schedule results :?: :?: :?:
     
  6. rockenroll

    rockenroll

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    No replicas boys :?: , is all about experience :D
    I wait for it...:cool:
     
  7. JohnD

    JohnD

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    Is this your homework?

    What do you mean when you say "CCU"?

    Are you familiar with the term "submain"?

    I'm very puzzled when you say "3 phase+n isolator BS 88 fuse 32Amps, thru 3x4mm single core conductors(phase,neutral,earth)..."
    3 phases but only got P+N+E?
     
  8. rockenroll

    rockenroll

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    CCU - Consumer's Control Unit :)

    I'm very puzzled when you say "3 phase+n isolator BS 88 fuse 32Amps, thru 3x4mm single core conductors(phase,neutral,earth)..."
    3 phases but only got P+N+E?

    Think that u have one CCU in one side and one 3P isolator in another side,
    from CCU u have 3 wire which feed the 3P isolator(P+N+E),the 3P isolator have 3 fuses BS 88-32Amps,the phase is getting through one fuse of 3P isolator(lets say-L1),(L2,L3-unused),from that fuse u feed now the ring final circuit (phase),u take the neutral from neutral bar (inside of 3P isolator) and earthing from earthing bar( inside of 3P isolator)
    I think that this will help u
    Cheers:cool:
     
  9. SparkyMarky

    SparkyMarky

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    Surely CCU = Cooker Control Unit
    CU = Consumer Unit

    That's the way I was taught - or is it just me? :confused:
     
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  11. JohnD

    JohnD

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    It's not just you.
    Nope.

    A 3-Phase isolator has P+P+P (or usually 3P+N)
    Earth is not switched.

    Can you draw what you mean in a diagram?
     
  12. holmslaw

    holmslaw

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  13. RF Lighting

    RF Lighting

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    BS7671 definitions:

    [​IMG]
    ;)
     
  14. SparkyMarky

    SparkyMarky

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    Well I can't argue with that...!

    I might start calling it a Electricity Control Unit or ECU for short instead though. I like the sound of that. It'll also have the added amusement of really confusing and worrying any petrol heads when I tell them I'm about to connect their ECU to the mains... :eek:

    (ECU = common TLA for Engine Control Unit for those who don't know ;) )
     
  15. rockenroll

    rockenroll

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    Holmslaw u right,this circuit could be taked as two circuits,or could be treated as radial at whole, if u make a note on schedule of test results about it:cool: , in special that I had readings as follow: for p-p loop 1.0 ohms, n-n 1.0 ohms, cpc-cps 1.0 ohms, and from 5 socket outlets just one had correct value, p-n and p cpc approximatly 0.52-0.51 ohms, others socket outlets fail with high values, the highest was 9.3 ohms, :idea: ATTENTION :idea: for who is taking practical assesment on C&G 2391, that inside of pvc trunking where the wires are runing they have fitted lots resistance to gave u high readings to see what u will write on PIR certificate, this happen in practical C&G 2391 PIR rig:cool:
    Have anybody meet something like this in practical C&G 2391 :?:
     
  16. 333rocky333

    333rocky333

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    Term often used in 15th regs days.
    When din rail fitted boards came out it was envisaged people would fit bell transformers,contactors, timers ,etc as well as mcb's within them.
    This one board would replace multiple single units.
    Hence Consumer Control, all located in one Unit.
    CCU
     
  17. rockenroll

    rockenroll

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    OK fellas, lets forget CCU and CU, any electrician express himself in his way, give remarks at that circuit, this is the main question...

    Cheers:cool:
     
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