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  1. P

    Domestic Reference method / routing guidance for cable on a wall with 25mm Celotex

    I wonder if anyone could assist with this query please ? I am a newbie, so any guidance or alternatives would be greatly appreciated. I need to run a ring final partly against a wall with internal 25mm Celotex type insulation. The additional Celotex being needed due to reduced cavity...
  2. happyhippydad

    Rings, reference methods and CCC...

    Following on from another thread I have just replied to it got me thinking about ring circuits and reference methods. Appendix 15 shows a ring on a 32A MCB. It does begin with a get out clause regarding thermal effects but it just points you Chapter 42 which deals with fire. If for example we...
  3. D

    Application of Installation Reference Method

    Hello All My query is about installation reference methods. Specifically how to choose a reference method where twin and earth cable passes through various conditions when none of the methods seem to fit actual site conditions. Site conditions are domestic situations where I find myself...
  4. happyhippydad

    What to put in 'Distribution reference' on forms?

    This is something I've been meaning to ask for sometime. What do you guys put for 'Distribution reference, or distribution reference number' on the forms? Sometimes there is what looks like a specific number on the CU, but more often than not there is nothing to distinguish a particular CU.
  5. ipd1961

    Quick reference guide for 18th

    Just completed the 18th Regs course and we were given a quick reference guide by the company delivering the course. I have redone it because there were a few typos and here it is in plain black and white or glorious colour
  6. M

    OSG, bonding plastic pipes etc etc

    Hi all Having a thumb through the OSG and on section 4.5 Main protective bonding of plastic services, it says there is no need to bond an incoming service of the service pipe is plastic....thats kind of a given....my struggle lies on the next page; "Where there is a plastic incoming...
  7. haptism

    Reference method for cable behind kingspan

    Hi, been looking at which reference method would be suitable in this case. The cable drops of a ring circuit to each socket are fixed direct to a concrete block wall (using capping) ; kingspan boards are to be dot&dabbed directly to the wall. Im thinking worst case would be ref method 102...
  8. A

    Reference Method Question

    Hi all, I'm not an electrician, just like to understand things for self learning. I was reading about how reference methods will derate the cable. However, either I have some misinformation or I am not fully understanding. Given the example of twin and earth, inside plastic conduit, buried in...
  9. A

    How to calculate the tabulated current (It) for circuits with multiple Reference Methods (A and B)?

    I am trying to select a suitable conductor size from Fig 4D1A of the BS 7671 Book, and am encountering a problem because the circuit does not conform to one Reference Method. The circuit conductors leave the distribution board in wall mounted steel trunking, then run through some steel conduit...
  10. Sparky_marky2

    SWA armour supply to outbuilding, what CSA cable? and Reference Method?

    Hi guys, I am running a supply to an outbuilding that requires a 22m run from the Main CU (in the garage) to the CU in the outbuilding, at the Main CU it will be a 40A MCB supplying an 63ma RCD protected sub board which will then supply: 6A type B MCB for 12 downlights and an extractor fan 32A...
  11. S

    What reference method

    Cables clipped to a brick wall with plasterboard dot n dabbed over them what reference method ? And any proof as ref c says clipped direct but nic inspector says that means just clipped to a wall the rest of the methods says insulation ?
  12. L

    Reference Methods??

    Hi there, I was just looking to find out what would be the most appropriate reference method to use. the distribution circuits leave the fuse board in 3 meters of trunking, then onto basket most of the ciruicts at lower lever then come down the wall in conduit which has been pre installed in...
  13. B

    Off grid earthing system

    What earthing system should be used on an off grid install with a solar inverter, wind inverter, battery backup inverter and a 4.5kW floating earth generator?
  14. S

    2357 portfolio HELP!

    Has anyone done NVQ 2357 portfolio with Ableskills? I'm just starting my portfolio bridge units 311 312 313 314 315 316 317 and 318 but really struggling how to start. It's really hard to understand the concepts of how they put their wording. My assessor doesn't explain it really well :(...
  15. H

    Voltstick Question

    I've got flu at moment so if this is a stupid/5ww/diy type question then illness will be my excuse :).... How do voltsticks sense live cables but not neutral cables?
  16. S

    4mm radial circuit

    I've just been flicking through the regs to do some cable calcs for a job and noticed that a 4mm 2 core cable installed using method B (under floors etc) has a capacity of 30A. However it is ok to connect to a 32A MCB for a radial socket circuit. Don't know if its just me missing something...
  17. tank

    rcbo functional earth

    hello, does the functional earth of a rcbo have value of loop impedance that has to be met in order for it to work as designed?
  18. S

    Installation Reference Method

    Hi What is the installation reference method for flat T&E cable, with capping and buried in plaster, am I correct in thinking it is method C as all the others in table F6 (page 150) in the OSG refer to insulation? Steve
  19. Q

    DC Volt Drop

    Has anybody got a chart for quick reference that can show me volt drop, i know the calculation but just wanted a quick reference table. Can any body help?
  20. F

    The new EICR

    Hi I wanted to see if anyone has any question or answers on the new EICR forms. I will start with, Does anyone know what "location reference" means in the schedule of inspections?