Heavy Duty Connectors

Heavy Duty Connectors, as a category, are quite robust, with flexible contact layouts, high sealing ratings, and high current ratings. They can, with all the available options, however, also be quite confusing. In this post, I’ll cover some basics of this connector category, and how to find all the pieces you would need for a complete connection system.


Heavy Duty Connectors generally consist of five basic components. Base, Hood, Male and Female Inserts, and Cable Glands.


Inserts can be housed in either the base or the hood, depending on the application. The female insert is typically used on the side of the connection that is providing power, to reduce the chance that the contacts can be touched while active.


The size of the insert is typically determined by the number of contacts, and the current carrying capacity of those contacts. Contact counts range from 1 to 108 positions, and contact current rating ranges from 0.5A to 650A, depending on the series.


Contacts in the inserts can be terminated in several ways. There are crimp contacts, which would come as a separate item, but there are also inserts with captive contacts, using screw, spring, or insulation displacement crimp (IDC) terminations.

Bases & Hoods


The size of base or hood you would need would be dependent on the size of the inserts selected. In the photo above, the inserts were size 24B, which matched the size of the base and the hood.

Cable Exit

Bases can be Bulkhead type, with the cable contained on the inside of the panel, or can be mounted to the exterior of the panel with exit points for cable glands at 90°.

Base Options

Hoods also have options for cable exit from the rear or from the side.


Latches can either be on the hood, or on the base, though they are more commonly on the base. There are also single and double latch options available, with double latches being the more secure option.

Latches are preinstalled, but we do have some locking latches separate from the housing in the Connectors, Interconnects > Heavy Duty Connectors - Accessories category.

Cable Glands

Cable glands would need to be matched to the thread of the hood or base, and would need to be able to accommodate the outside diameter of the cable you will be using. For more information on cable glands, please see the posts Cable Gland - Function and Key Parameters and Cable Gland Thread Differences - PG vs NPT vs Metric.
They are available in two separate sections of the Digi-Key website, Cables, Wires - Management > Cable and Cord Grips and Connectors, Interconnects > Heavy Duty Connectors – Accessories.


In the introduction, I had mentioned that Heavy Duty Connectors are flexible in contact layout. Using frames, such as those found in the Connectors, Interconnects > Heavy Duty Connectors – Frames category, smaller insert modules can be inserted and arranged in a custom manner in larger bases and hoods.

Modules for this are usually in the Associated Products section of the frames, but can also be found in the Connectors, Interconnects > Heavy Duty Connectors - Inserts, Modules category.


Digi-Key does also have complete Heavy Duty Connector assemblies available, shown on the following link:
Some of these would still require the cable glands be purchased separately, but do include the base, hood, and both inserts.