2. The plaintiff's assertion

A. The equipment supplied by the Defendant due to the defect was defective due to disregarding the requirements required by the Plaintiff, and due to such defect, the product supplied by the Defendant to the Saudi Arabia site was returned to the Defendant.

The Plaintiff cancelled the instant contract by serving a preparatory document dated July 9, 2013 on the ground of the defect in the instant equipment.

B. The plaintiff following the delay of performance did not agree to pay the progress payment or the part payment to the defendant in addition to the payment method stipulated in the contract of this case.

The defendant violated the second payment period due to the reasons attributable to the defendant, such as the failure to pass the performance test at the Korea Electric Research Institute.

Accordingly, the Plaintiff notified the Defendant to perform the contract on July 14, 201 and extended the delivery date to October 18, 201. However, on September 22, 2011, the Defendant supplied approximately 40% of the unpaid equipment of this case, and delayed the supply of the remainder of equipment, and rescinded the instant contract on October 19, 201.

C. The Defendant should return to the Plaintiff the advance payment, etc. received from the Plaintiff due to the instant contract, due to the cancellation of the instant contract for restitution.

3. Determination

A. (1) Evidence Nos. 9, 10, 12, 35, 39, 41 through 46, Eul evidence Nos. 5, 6, and 7 (the number of pages is included; hereinafter the same shall apply) due to the defect of the instant equipment

According to the following facts which are acknowledged as a whole by integrating the purport of the entire pleadings, the equipment of this case is manufactured differently from the specifications presented by the Plaintiff, or there are parts requiring additional supplementation.

① The Defendant on January 25, 2010 pertaining to the instant equipment from the Plaintiff.