one of these is great to use they don't cost much but only work in 110 lines you can search the UK site for one that works on 240 line but good luck getting it shipped to the US if that's were you live . some kind safely issue won't allow it .


https://www.amazon.com/s/?ie=UTF8&keywords=kill-a-watt+meters&tag=googhydr-20&index=aps&hvadid=31006933645&hvpos=1t1&hvnetw=g&hvrand=17391202976933736560&hvpone=&hvptwo=&hvqmt=b&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9007872&hvtargid=kwd-6896404661&ref=pd_sl_6pbqdkbvd3_b


my bad

https://www.amazon.com/Electric-Meter-100A-Volt-3-Wire/dp/B00GMZRXE8/ref=sr_1_12?ie=UTF8&qid=1478811987&sr=8-12&keywords=kill-a-watt+meters this one will work on a 240 is buy able in the US now .

but direct pulling into a 240 so far there is not one that it buy able in the US the buy able US sold one only plug in to a 110 wall plug the above monitors your hole house.