Hi all,
Currently quoting for a fairly extensive remodel of a kitchen diner, and I have a couple of things I'd appreciate a sanity check on.
1. Structural steel bonding - My brain is telling me based on what I've read and understood that I don't need to bond the new structural steels. They aren't in contact with the ground, but my heart is telling me that just seems wrong somehow. One of the beams is going to have it's cavity acting as trunking effectively since it's the path of least resistance from one side of the room to the other and so my thinking is, I should bond it to ensure a good earth path in fault conditions.
2. Sanity check on a cable size - New oven, 22.2A (max, no diversity factored in at all). 6mm can handle it, but obviously running a 20A breaker at that is not great long term, so 32A breaker required. Since 6mm can only handle 27A when in a ceiling with insulation (ref method I'm going to be encountering), my only choice is 10mm. Voltage drop is fine either way, it's just the potential overload situation. So 10mm is the correct choice as far as I'm concerned.
3. There is going to be some under cabinet lighting. To future proof, I am going to suggest that the supply for this (coming from a 6A lighting circuit) is exposed in the cupboards as 13A unswitched outlets since then the customer can change the lighting to their hearts content. My concern though is if they stick something other than lighting on it. 1.5mm is fine generally, and can handle 13A in the ceiling with insulation. So my brain is saying this is fine, but for some reason it just feels wrong. For that reason I was considering providing the supply by 5A round pin outlets, but that raises the issue of the 6A breaker. I have very limited experience of round pin outlets. 5A is obviously the continuous rating, try as I might, I can't find any information about overload characteristics, so I'm wondering what you guys think?
Whilst it's a fairly big job (by my standards so far), the rest of it is straight forward, it's just these three niggles I could do with a bit of feedback on.
Comments and thoughts welcome
Currently quoting for a fairly extensive remodel of a kitchen diner, and I have a couple of things I'd appreciate a sanity check on.
1. Structural steel bonding - My brain is telling me based on what I've read and understood that I don't need to bond the new structural steels. They aren't in contact with the ground, but my heart is telling me that just seems wrong somehow. One of the beams is going to have it's cavity acting as trunking effectively since it's the path of least resistance from one side of the room to the other and so my thinking is, I should bond it to ensure a good earth path in fault conditions.
2. Sanity check on a cable size - New oven, 22.2A (max, no diversity factored in at all). 6mm can handle it, but obviously running a 20A breaker at that is not great long term, so 32A breaker required. Since 6mm can only handle 27A when in a ceiling with insulation (ref method I'm going to be encountering), my only choice is 10mm. Voltage drop is fine either way, it's just the potential overload situation. So 10mm is the correct choice as far as I'm concerned.
3. There is going to be some under cabinet lighting. To future proof, I am going to suggest that the supply for this (coming from a 6A lighting circuit) is exposed in the cupboards as 13A unswitched outlets since then the customer can change the lighting to their hearts content. My concern though is if they stick something other than lighting on it. 1.5mm is fine generally, and can handle 13A in the ceiling with insulation. So my brain is saying this is fine, but for some reason it just feels wrong. For that reason I was considering providing the supply by 5A round pin outlets, but that raises the issue of the 6A breaker. I have very limited experience of round pin outlets. 5A is obviously the continuous rating, try as I might, I can't find any information about overload characteristics, so I'm wondering what you guys think?
Whilst it's a fairly big job (by my standards so far), the rest of it is straight forward, it's just these three niggles I could do with a bit of feedback on.
Comments and thoughts welcome
