Cable Glands and Connectors: The Weak Point in Every IP Rating

Almost every IP failure in the field traces back to a cable entry. Enclosures are tested as sealed boxes; installations add holes, glands and connectors that were never part of that test.

Gland ratings

Glands carry their own IP rating, and it depends on the cable diameter range they are used with. A gland rated IP68 with a 6 to 12 mm cable is only IP68 at 6 to 12 mm; using it with a 5 mm cable leaves a gap that the seal cannot close.

Installation

Tighten to the manufacturer torque, not by feel. Water enters along the cable jacket when the seal grips the jacket too lightly, and along the conductors when the inner seal is missing. Fit a drip loop so water runs off before it reaches the gland.

Testing entries

Test the assembly with the entries fitted, in the orientation used in service. A test on the empty enclosure proves the box, not the installation. Where connectors are used, check that the mated pair is rated, since many connectors lose their rating when unmated or when a different series is mated to them.

Related technical notes

• IP Code First Digit: What 0 to 6 Actually Tests
• IPX1 and IPX2 Drip Test: Tilt, Flow Rate and Duration