Tips On Selecting Connectors

There are dozens of connector varieties and thousands of individual connectors, so even an experienced engineer can find it difficult to select the right connector for the job. Fortunately, connector confusion can be minimized by gathering information based on four key technical factors.

Connector Data

There are many types of connectors and it can be difficult to select the right one for each application. While they add a small premium to the initial cost of cabling, they will pay for themselves if they eliminate a few minutes of downtime on a busy production line.

-Number of contacts: The number of contacts in the connector should match or exceed the number in the cable. But one common mistake is to miscount by not considering the ground. Cable conductor counts typically include ground while connectors do not.

-Wire gauge (awG): The cable wire gauge needs to be within the allowed range of the connector contacts. In general, screw contacts will accommodate a broader range of wire gauges than comparable crimped contacts.

-Cable outside diameter (OD): This fundamental piece of dimensional information is too often overlooked during the specification process. Forgetting OD can have serious consequences. If the OD of the cable is too small relative to the housing, a poor seal will result, creating a performance issue. If the OD is too big, the cable may not fit in the housing easily or at all, creating a potentially costly installation issue.

-Maximum voltage and current: Double check to make sure the application’s voltage and current are within the rated capacity of the connector. For safety, this is the cardinal rule of specifying connectors.

Taken together, these factors determine whether the connector will function as a true extension of a given cable. It’s important to emphasize that all four factors must be taken into consideration. A connector, for instance, may meet the requirements on a number of contacts, wire gauge, and outside diameter, but not satisfy the application’s current or voltage requirements.

The four key connector factors should be thought of as a starting point. They don’t capture the effects of difficult operating environments or unusual electrical requirements. But, they will help you quickly narrow the otherwise overwhelming fied of connector products.

Jack Gayara
Connector Product Manager
Lapp USA
Florham Park, NJ