However, when the number of primary windings of the main transformer is increased to form two parallel primary windings, for example, two inverter output cables for each round trip, that is, {HEAD ~ a total} of {TAIL ~ four cables} are required 
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However , when the number of primary windings of the main transformer is increased to form two parallel primary windings , for example , two inverter output cables for each round trip , that is , { HEAD ~ a total } of { TAIL ~ four cables } are required
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