conduit 150mm
https://kilo-wiki.win/index.php/Choosing_the_Right_Low_Voltage_Garden_Cable_for_Safe_Outdoor_Wiring
When running 150mm conduit underground for heavy-duty electrical or data cables, the wider diameter makes pulling multiple lines through bends far easier and reduces the risk of damaging insulation. This size is common in commercial or industrial settings where future expansion might be needed, so the extra space in the pipe can save a lot of headache later.