In brief
A second source is a second, equivalent source of supply for a component that secures supply if the main supplier fails or faces a shortage.
Contents
What is Second source?
A second source is an additional supplier or manufacturer that can supply a technically equivalent part. The term originally comes from electronics, where components were manufactured under licence by several manufacturers. It is to be distinguished from dual sourcing, in which two suppliers permanently receive volumes in parallel: a second source may merely be qualified and only activated when needed.
A distinction is made between a second source for the same original part, such as another authorised distributor, and a second source for an alternative part from a different manufacturer. In the second case, equivalence must be demonstrated, usually by comparing form, fit and function, data sheets, materials and, where applicable, approvals. Only after this qualification is the source considered approved.
In spare parts supply, a second source reduces the risk of supply shortages, discontinuations and price jumps at the single supplier. However, it involves effort for testing, master data maintenance and supplier evaluation. It is therefore worthwhile above all for critical spare parts and components with long replenishment lead times.
In practice: maintenance and procurement
To qualify a second source, the manufacturer part number, data sheet, drawing, material details and required certificates should be available. Approved alternatives belong in the master data with the approval date and any restrictions, so that they can be ordered in the event of a breakdown without a fresh review.
Synonyms and abbreviations: second sourcing · alternative source of supply · secondary supplier · backup supplier
Frequently asked questions
What is the difference between a second source and dual sourcing?
In dual sourcing, a company permanently splits its ongoing demand between two suppliers. A second source, on the other hand, does not have to supply regularly: it can be qualified and approved but only come into use in the event of a failure, shortage or discontinuation at the main supplier. Dual sourcing is thus one way of actively using a second source.
How do you qualify a second source for a spare part?
First, the technical requirements are defined: dimensions, connections, performance data, materials and necessary approvals. Then the data sheets and drawings of the alternative are compared, samples are checked at goods receipt or in trial use if necessary, and the supplier is evaluated. The result is documented so that the approval remains traceable.
For which parts is a second source worthwhile?
It is particularly useful for parts whose failure brings a plant to a standstill, for long replenishment lead times, for parts offered by only a single manufacturer and for components facing foreseeable discontinuation. For inexpensive standard parts with many suppliers, on the other hand, the qualification effort is usually not justified.