@flameport - Thanks for the reply.
Probably, but it also depends on the length of the duct and if there are any bends in it.
My first post may have been inaccurate as I stated that the cables would be running to an inverter which may not be true as I may be installing some form of battery set up so I believe that the cable would run to a controller before the batteries and inverter?
The DC cables start at different locations and run as follows....
A. Bank A will be 4m unducted in a cold loft then a bend into 4m 32mm ducted, this ducting will be surrounded by insulation in a plasterboarded ceiling but either end of the ducting will be open to the cold loft air.
B. Bank B will be 4m unducted in a cold loft,
C .Bank C will be 5m unducted in a cold loft,
D. The separate DC cables will then run through a single 32mm ducting of 2m (this ducting will be surrounded by insulation in a plasterboarded ceiling.) followed by a bend followed by a further 3m of 32mm ducting (this ducting will be in a plasterboarded stud wall but will NOT be surrounded by insulation) before entering the garage where they will exit the ducting and will continue for a further 2m unducted surface mounted on the internal garage wall .
The bends will not be ducted.
So longest run is for bank A will be approx. 15m.
I do have the option of combining the DC cables at point d within an accessible junction box into larger cables and running these through the ducting if that is allowed.
I may also have the option of placing the controller and/or the batteries and/or the inverter in the loft which could reduce the longest DC cable length to around 8m of which 4m would be ducted. I would then run 16mm? AC cable to the garage where my consumer unit is located.
I do already have a bank of 4kw on my existing house and this has 2 4mm cables that runs to the invertor. I have attached a photo.
I appreciate that it would make sense to get an installer on site to advise me but I am building a house pretty much by myself and the time scales between jobs can be excessive and hence installers are not keen to come out for a job that may not take place in the near future.
Any help much appreciated.
