The galvanizing of steel wire, both the hot-dip and electroplating processes, is described in
The Making, Shaping and Treating of Steel, 9th Edn., pages 856-860 (1971).
Electro-galvanizing [the term used in the book] has the disadvantage of being a slower process for the same thickness as hot-dip; hence, a longer tank (100 feet) is required.
Advantages: Electrolytic zinc is more ductile than hot-dip zinc, especially for greater thickness, due to the FeZn
n intermetallics formed in the hot-dip process. Also, the electrolytic thickness is more readily controlled.
For more information on electroplating of zinc on steel, see
'Metal Cleaning,' 'Pickling and Acid Dipping' and 'Zinc Plating' at
ASTM B633-98e1 'Standard Specification for Electrodeposited Coatings of Zinc on Iron and Steel' covers zinc electroplating in general, but not onto sheet (see ASTM A591) or wire (no ASTM standard). However, there are at least 5 ASTM specs for hot-dip galvanized wire, e.g., ASTM A854.
Hope this helps,
Ken