Hitachi H20-T Technical Notes page 44

Th e 3-elem ent t h erm a l over load r ela y is so a djusted t h at it ca n n orm a lly opera t e in a sta t e wh ere cu r ren t flows t o
a ll 3 elem en ts.
In t h e case shown in F ig. 41, t he pr ot ect ion ch ar a ct er ist ic is deter ior a ted.
Th e pr otection ch ar a cter ist ic in dica tes a deviat ion of 12% in t h e worst ca se as sh own by t h e dot ted lin e in F ig. 42.
F ig. 42 Oper at in g ch a r act er ist ic in wr on g con n ect ion
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