Hi colin,
cheers for your quick reply, Im afraid I have extremely basic knowledge of electronics, but like to think im a good electrician
(-; So im hoping if someone gives me pretty laymen terms, I might just be able to answer. So assuming I have interpreted your queries correctly
1) The voltage drops in relation to the wattage, i.e more wattage less voltage. But does vary daily, i.e some days I can use 4KW with minimal volt drop. Possibly due to other users on my network from the substation.
2) I only have 220V single phase
3) I do not have such a transformer, but if it could cure my problem, I guess I would try & order 1
Thanks again