First post and I'm looking for some advice if someone would be so kind.....I am a qualified electrician but it's been a long time (17 years) I've been in management so be kind ![Upside-down face :upside_down: 🙃](https://cdn.jsdelivr.net/gh/twitter/twemoji@14.0.2/assets/72x72/1f643.png)
I'm looking for some advice I have an outbuilding that I wish to run a cable to. The cable I ran is a new 16mm2 2 core steel wire armour buried in soil it currently runs to the edge of the main building, it's 25m long.
The problem I have is getting a cable to the edge of the main building internally approx 10m from the (TN-S) supplied main board.
I can think of three choices (without major disruption)
1) there is an existing 20mm plastic conduit plastered into the wall, one thought was using a 16mm2 3 Core SWA and strip it back to the singles and use that existing drop which would only be the last two meters of the run. I haven't got any to check but I don't think the inner round sheathing would fit down a 20mm conduit?
2) Drop that last 2m down the cavity (yes I know....)
3) Down the outside of the building (asthetically would not look good)
No option is ideal but without major upheaval I can't think of another way. Any suggestions would be greatly appreciated.
Obviously cavity isn't ideal due to unsupported cable and potential thermal derating due to insulation but it's NOT polystyrene. It would be going down so no potential to transfer damp.
The conduit method is obviously reducing the mechanical protection of the cable and possibly reducing its thermal dissipation properties.
Second question is when I do get a cable in place what options do I have for joining in an enclosure attached the outside of the building? The outbuilding has an EV charger attached and living annex accommodation so would likely need the installation to hold maximum 64A I have never seen terminals rated for such a load.
I have looked everywhere and cannot find a reference method for singles in plastic conduit to calculate the cable. I know under normal circumstances that SWA would support a higher current but I intended to derate accordingly.
My ability to sign off the work has long expired so I'm just doing the donkey work and a colleague will inspect and test the installation.
![Upside-down face :upside_down: 🙃](https://cdn.jsdelivr.net/gh/twitter/twemoji@14.0.2/assets/72x72/1f643.png)
I'm looking for some advice I have an outbuilding that I wish to run a cable to. The cable I ran is a new 16mm2 2 core steel wire armour buried in soil it currently runs to the edge of the main building, it's 25m long.
The problem I have is getting a cable to the edge of the main building internally approx 10m from the (TN-S) supplied main board.
I can think of three choices (without major disruption)
1) there is an existing 20mm plastic conduit plastered into the wall, one thought was using a 16mm2 3 Core SWA and strip it back to the singles and use that existing drop which would only be the last two meters of the run. I haven't got any to check but I don't think the inner round sheathing would fit down a 20mm conduit?
2) Drop that last 2m down the cavity (yes I know....)
3) Down the outside of the building (asthetically would not look good)
No option is ideal but without major upheaval I can't think of another way. Any suggestions would be greatly appreciated.
Obviously cavity isn't ideal due to unsupported cable and potential thermal derating due to insulation but it's NOT polystyrene. It would be going down so no potential to transfer damp.
The conduit method is obviously reducing the mechanical protection of the cable and possibly reducing its thermal dissipation properties.
Second question is when I do get a cable in place what options do I have for joining in an enclosure attached the outside of the building? The outbuilding has an EV charger attached and living annex accommodation so would likely need the installation to hold maximum 64A I have never seen terminals rated for such a load.
I have looked everywhere and cannot find a reference method for singles in plastic conduit to calculate the cable. I know under normal circumstances that SWA would support a higher current but I intended to derate accordingly.
My ability to sign off the work has long expired so I'm just doing the donkey work and a colleague will inspect and test the installation.