1. The apprentice

    wylex mcb

    K7665sMET this is the product code if you google it will show you the consumer unit not sure what type of mcb would go in this wylex board
  2. U

    Neff Oven tripping MCB

    My Neff double oven is tripping the MCB on the mains. This occurs when I switch on any function of the top oven. The model is U1744N (around 15 years old). The top oven has a double element at the top (grill and oven) with a second element under the casing at the bottom of the top oven. The...
  3. S

    Schneider RCBO to replace MCB

    Hello, I am currently working on a project that previously utilises a charger for a battery system that is connected via single phase 240V AC mains. The existing charger has the 15A inlet running through a 1P 16A schneider MCB with the active line connected to the MCB (with earth and neutral...
  4. J

    Other electrician replaced RCBO with MCB

    Was called out to a car park where they had the lighting circuit tripping out. Fixed the issue by putting damaged cables in an IP rated box. However just realised that the electrician who came out before myself took out the RCBO and replaced it with an MCB in hope that it would stop tripping...
  5. T

    Is what I've done any good/safe?

    Hi everyone, I've come here as a DIYer asking for professional advice/opinion. I have an 8.5KW shower on a 6mm cable and a 40amp MCB. The shower works fine........for about 8 minutes! It invariably trips out. Sometimes it lasts 6 minutes, sometimes it lasts 10. I was considering changing the...
  6. H

    Short circuit bypasses mcb and trips submain mcb

    Good evening A cable was loose in a ceiling void causing a short circuit this didn't trip the 10 amp 6ka type b mcb but tripped the 50 amp type b 6ka mcb that supplied that board back at the mains. I am wondering why this occurred other than me thinking the local protection isn't very...
  7. T


    I have isolated the MCB feeding my garage when switched on trips the RCD. There is no load on the garage I have an internal switch in the garage that switches all circuits off. So the fault must be between the MCB and the garage switch. The armoured cable is under the patch so to dig up would be...
  8. F


  9. I

    Radial circuit from 20A MCB

    Not sure if this is possible but just putting it out there... Current Situation Need to tidy up some of the mess in the garage from the previous owner of the house. Wires going all over the place. Additionally, all of the upstairs lights, the garage light and an external light are all radial...
  10. M


    Hello, Could you please help me, I would need to install Triton T40i Bath/Shower Mixer Booster Pump, this is a "booster shower" only and not an "electrical shower" whose specifications are as follows: Electrical Voltage: 240V Pump motor rating:73 Watt (nominal) Water Inlet connection ½” BSP...
  11. S

    UK Advice needed! Ive been to see a job for garage power, the previous electrician has taken a 4mm on a 32amp B MCB protected by a 30mA RCD. But hasnt do

    Advice needed! Ive been to see a job for garage power, the previous electrician has taken a 4mm on a 32amp B MCB protected by a 30mA RCD. But hasnt done anything with, apart from the fact there is no protection and its T&E all straight forward. My ownly question is do i gland straight into a...
  12. Iain Stewart

    UK Inspection Report, Electric Shower, Merlin Gerin and Schneider MCBs

    Hello, We live in an old stone built ground floor flat, built in the 1880s. Obviously the consumer unit and cabling has been updated a number of times over the years by previous owners. One being the Local Authority who owned the property back in the 1960s -70s. We have lived here for 25 years...
  13. GBDamo

    Ramp testing an MCB

    Is there an over the counter device for this? Is it something that is done outside of a lab? Been asked a few times, how do you know it'll trip. Or when forced to use second hand MCBs it would be nice to check them.
  14. J

    2KW oven and 6KW hob on B32 MCB

    Can a 2kw (on a 1.5mm manufacturers flex) fitted oven and a 6kw hob (on a 2.5mm manufacturer's flex) be connected into a cooker outlet plate behind the cooker? The circuit is wired in 6mm t&e on B32 mcb. It has a 45A cooker switch with 13A socket in the kitchen (within a metre of the appliances)
  15. T

    Main RCD Tripping & Not MCB

    DIY expert tried changing his own Consumer unit from an old 3036 re-wireable CU to a 18th Edition (100A main switch / 63A 30mA RCD / 7x MCBs) I was called out because he couldn't get his sockets (ring main) back on - NEITHER CAN I, I HAVE TRIED EVERYTHING I THINK... The Lines are terminated...
  16. B

    UK Oven trip MCB

    Hi all, I’m hoping someone will be able to give me some advice on my oven. Tonight I had both ovens on (as has been done on several occasions). When I went into the kitchen about 10 minutes later I noticed the oven was off and had tripped the 32Amp MCB. I reset it at the CU and it came back on...
  17. B

    UK RCD vs MCB trip

    Evening everybody, I’m wondering if someone wouldn’t mind answering a question for me about RCDs. I had a water pipe burst behind my washing machine this evening, and once I’d isolated the leak I noticed the sockets had tripped. When I went to reset the breaker, I noticed that it was the RCD...
  18. J

    RCD vs MCB...

    Does an MCB protect against fault current in the same way as an RCD does? As in, both devices trip by way of detecting imbalance in the Line conductors and thus using magnetism to sprag the switch? I ask, because if so, I can’t get my head round why an RCD is better than an MCB. I know that it...
  19. L

    No end to end 2 Radials on one MCB

    Hello, I have tried to search the forum but have not found anything although this must have been asked a thousand times. When completing a board change for example and there is no end to end on the neutral does downgrading the mcb to a 20amp and effectively running two radials from the same MCB...
  20. N

    Tripping mcb and rccb

    Hi guys. Just want some advice or thoughts from the pro's. So I'm an engineer who works on espresso machines. Going back a few months ago now I got called out to a machine tripping the power, in my line of work this generally means one loop on the heating element has shorted to ground or one...
  21. N

    Why would spike lights trip an MCB as if a dead short is present ?

    Just finished installing 20 x spike lights in a customers front garden. 2.5mm SWA ran from existing junction box feeding existing fence lights. All pulling no where near 1A in total. When all connected and wiring tested, went to switch on MCB and it popped. Rendering the MCB useless as if L-N...
  22. J

    Looking for electrician to swap MCB in OL10 area.

    Hi. Im looking for electrician to swap mcb in my consumer unit for one suitable for single phase welder with max input current of 16A. In my consumer unit there is 32A type B mcb that was used with electric shower that is disconnected. I need it swapped for 16A type C (been told its a right...
  23. Z

    MCB trips ONLY when open in one go all lights together

    I have about 50 led spot lights + more light , all together is about 400w if I open them all in one go together, then the MCB [=6 am] trips immediately, but if I open them one by one I have no problems at all ! I tried to replace the MCB with another 6am and it did the same, but when i replace...
  24. buzzlightyear

    need max for old mcb

    any body got the max ohms for old dorma smith mcbs , I asked dorma smith years ago sent me max ohms for old load masters .
  25. F

    Industrial C50 MCB

    Does anyone know where I can get an old Crabtree C50 type MCB from?
  26. M

    Intermittent mcb trip electric gate

    Hi, just registered, I qualified in 1973 and and not done much electical work for the past 30 odd years but I obviously have grasp of the theory. I have an intermittent mcb tripping on my electric gate, which I installed. (All electric no hydraulics) The mcb will trip in any weather...
  27. N

    6mm T&E on 40 amp mcb

    while doing EICRs i often find this combination, if its clipped direct it dont worry me however many times i have no idea how the cable is routed im just wondering how others would code this?
  28. K

    Need a different mcb

    Hi al it’s not. DIY job I’m aware of that. But I have just purchased an electric range cooker. Had an electrician out to extend cooker cable and he told me the instructions Manila of the cooker required a 40amp MCB. I’m not really in the market as of yet to be changing the consumer unit and I...
  29. Ashley-Joseph

    Spur from 32MCB

    Just wondering if I got this right but is it ok to take a 2.5mm spur from a 32MCB ring main Or should I use 4mm cable.
  30. coolsparx

    Old Crabtree Starbeaker MCB Compatibility

    Does anyone know if the current Crabtree 61/B32 Starbreaker 32A SP 6kA Type B MCB will fit the old board pictured?
  31. J

    Wylex Stotz PSB 63A MCB

    Does anybody know where I can source an old style Wylex PSB 63A SP MCB? It's to fit an existing 3 Phase Distribution Board with fork style busbar. Thanks in advance.
  32. A

    Domestic Oven won’t work...unsure issue.

    Hello, My cooker (LOGIK LFTC60W16 oven with grill and 4 hobs had it maybe just over 2 years) stopped working about 2 weeks ago. I found out we have no cooker switch on the kitchen wall so checked the Circuit Breaker box. Everything was on. With no other option I left the cooker MCB switch in the...
  33. The Flyinhos

    Cheap MCB lockout devices

    Had these arrive today, thought it was quite a bargain. 10x lockouts for £9.00 including VAT and delivery. Thought they maybe cheap n nasty, but pleasantly surprised. Can't knock em for the money.
  34. W

    Body’s resistance with mcb only

    If there’s 230v and the body’s resistance is high .. Meaning the current will be very low but enough to kill you. Can we get electrocuted without having a 30ma rcd to stop this as the 6amp breaker will not have tripped ?
  35. Marcus Vaughan

    Type C MCB needed for EV Charging?

    Hi all, I've not a lot of experience with EV but was called to a local job to investigate a loss of power to a 32amp 7.2KW EV charger. It turned out the 32A MCB (Type B) had failed, and would not even operate when completely removed from the board. I happened to have a matching Contactum B32...
  36. T

    Lock Off Device for Triple Pole Main switch & MCB

    Hi all. I am undertaking an assessment next week called SAFE ISOLATION OF SUPPLIES. It involves isolating and securely locking off a circuit to be worked on. The 4 items to be isolated is THE WHOLE INSTALLATION, A 3 PHASE CIRCUIT, SINGLE PHASE CIRCUIT & LOCAL ISOLATION (which is an isolator...
  37. T

    Domestic Type of MCB .........................

    In domestic when the Zs easily low enough why do we default to have type B instead of C curve MCB's/RCBO's
  38. R

    Sub panel: Underrated MCB?

    Hello all A quick question about an existing layout if I may. The layout consists of a main CU connected to a sub panel via a single 63 amp MCB. A Dorman Smith K1PC63 to be exact. Total potential load on the sub panel is 25Kw. Routinely all of that load is present on the sub panel...
  39. C

    Max zs on double pole mcb

    I am filling out test sheets and have a merlin gerin D32 C60 HD double.pole mcb. The rating on the mcb says 415V feeding 2 feeds to a canalis busbar. BS7671 States max zs for D32 0.4 secs is 0.34. Is this just for single pole MCB? I have also check my max zs value from manufacture stating...
  40. C

    Appliance tripped MCB after....

    Carried out an eicr and noticed x2 double sockets have reverse polarity that supply a frying machine at high level. (this was a return visit to correct the faults) After correcting the reverse polarity on the two sockets i plugged the fryer back in and the circuit MCB tripped out and the...
Top Bottom