[1] DIN4753-3:2013,Waterheaters,waterheatin ginstallations and storage water heaters for drinking water-Part 3:Corrosion protection on the water side by enamellingand cathodic protection-Requirements an testing” [S].DIN,2011.
[2] AS/NZS 4692.1:2005,Electric water heaters Part 1:Energy consumption,performance and general requirements[M].Australian/New Zealand Standard,2005.