Armoured Cable size

Anyone needing to ask basic circuit design questions such as cable sizing needs an electrician to come and carry out other design considerations such as voltage drop, over current protection, additional protection and bonding requirements. Please get an electrician involved, there’s a lot more to it than just choosing the right cable and if you need to ask you’re in over your head. Think of it like this, do you know the installations Ze, can you carry out a Zs calculation, can you measure IR? Because that’s not even the half of it. You should ignore the other guys advice, they don’t even know that 1.5mm isn’t the smallest SWA size available.

You Really need the advice of an Electrician. You will need to know the wattage of the pumps and work out volt drop for the length of run, calculate a suitable protection device and RCD protection, also what circuit and/ or Consumer unit this will be connected to etc. Also you need to know how to terminate SWA correctly. Not a DIY job.

The smallest SWA size in the BS7671 wiring regulations is 1.5mm2 as listed in the current carrying capacity tables, 4D4A and 4E4A .

A 2.5mm2 3 core swa cable is perfect for the job. However there are other things to take into consideration , depth in which cable is to be buried , protection for circuit and weather proof socket or switch spur also how to terminate the cable correctly. Job needs to be certified as well.The customer need to get some one out to advise them.