Correct

空载

/ kōngzài /
Strokes

Definition

(of a ship, train etc) not carrying any load (i.e. no passengers or freight etc)/(electricity) no-load (used to describe the condition of a transformer when there is no load connected to its secondary coil)

Example

As a Verb

(of a vehicle or a piece of equipment) operate without load

1
Kōngzài
空载
yùnzhuǎn
运转

no-load running