Home |
Search |
Today's Posts |
|
UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions. |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to uk.d-i-y
|
|||
|
|||
Design Current and Type B/C MCBs
I'm converting my garage to a small woodworking
workshop. I need to install a CU in the workshop and run a cable from the house CU. As it happens the house CU will be replaced at the same time. I know how to do the cable calc, but I'm struggling with two aspects. One is understanding what I use for Ib (Design Current), the other is to do with Type B / Type C MCBs. Design current first. ----------------------- This is design current of the workshop. I'm not using diversity because I am very clear about what the max current will be and that it will occur. What I don't know, is what to do about motor startup currents. Do I have to take them into account for Ib? Some of the machines (Eg.. 3Kw Hammer Sawtable) have soft start so I imagine the startup currents are handled by the electronics in the machine. Others, like the 2.2Kw Axminster ADE4000 Dust Extractor don't have soft start. Axminster have told me that I should double the running current and add another 15% in cold weather. MCBs ------- My thinking is that I may need Type C MCBs in the workshop CU. I am really gozzy on the differences/benefits/requirements re Type B and Type C. My only understanding (apart from the various graphs/charts in the Regs) is that the Type C is less sensitive to startup currents. How do I determine if Type C MCBs are needed? Also, if I have Type Cs in the workshop, does that mean that I must have a Type C for this circuit in the house CU. If so I think I might have to run a separate (larger) CPC to satisfy the Shock Protection requirements. Thoughts? Oh - and BTW - I know about Part P - before we go down that route!!! :-) Many thanks, Roy |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Tub drain: Standard lever type vs pop up type | Home Repair | |||
Electric hob prewired with 13A plug. | UK diy | |||
My shed & garage electricity supplies & earthing! | UK diy | |||
15A Circuit Breaker on a Power Tap | Electronics | |||
Lighting circuits and MCB's tripping | UK diy |