Truncated Sequential Sampling Plans of Electrical Products Having Two Failure Modes

It is of great significance to design an economic sampling plan for the electrical products in mega engineering projects. The existing traditional plan normally considers single failure mode of the item being inspected. However, the major products in mega engineering projects usually have different failure modes. To overcome the drawbacks of traditional plans, a truncated sequential sampling plan of electrical products having two failure modes is proposed in this paper. The newly proposed sequential sampling plan takes two different failure modes of an electrical product into consideration, consisting of the sequential sampling scheme for soft-failure mode and the sequential sampling scheme for catastrophic-failure mode. The concept of cut-off line is introduced, limiting the sample size within a certain range. At last, a numerical example is provided. This newly proposed sequential sampling plan provides a reference for the design of economic acceptance sampling plans for expensive electrical products and the products with multi-failure modes.