L-com carries a lot of stuff. In fact, the L-com web site boasts over 15,000 unique product pages. But among all those varied parts, one of the most popular items fits in the palm of your hand and weighs approximately 1 oz. What is it? An Ethernet jack! Here, we're going to talk briefly about Ethernet jacks, but don't miss L-com's exclusive video on the topic!
A "jack" is the term we use for female connectors. A jack is often mounted on something so you can easily patch or plug in a cable when you need to. RJ45 jacks are used to terminate the twisted-pair wiring in a wall or device to a convenient point so you can plug your computer or networked equipment in easily. If you look around your office, you're very likely to find wall plates with female RJ45 connectors or "jacks" mounted in them.Jack Options
There are two main questions to ask when you know you need an Ethernet jack: where is it going to be mounted and what type of cable is it terminating. You need to know how you want to mount it first. Are you mounting to a wall plate or panel? How thick is the mounting plate? Do you want it to be extra stable in case someone abuses the port? Does it need to be water/dust resistant? Next, you'll have to know what you have behind the jack. Is it shielded cable? Is it category rated? Is it already terminated with a plug (male connector)?
The easiest place to start is to consider how you want to mount the jack. One method is the "keystone" style. These jacks come with a spring retainer on the bottom and a fixed retainer on the top. Mounting them is usually quick and easy (see a video here). Also, there are plenty of keystone style wall plates to choose from. However, there are a couple of sacrifices for using keystone style jacks:
- The "keystone" style isn't independently standardized, so if you are using products from different manufacturers you risk them not fitting correctly
- The retainers aren't foolproof; someone who abuses the jack by jamming the plug in too harshly may push the jack out of its mounting plate
- The plate that you mount the jack to must be around 0.062" (about 1.5mm) or less; any larger, and the clips may not hold
If any of these factors are a problem for your application, you may want to consider upgrading to L-com's "ECF" style flange-mount couplers. These jacks have a flange on the top and bottom that can be securely screwed to your plate or panel. This increases the stability of the jack and allows you to mount to virtually any panel thickness without problem. You can also combine the keystone and ECF styles with handy ECF/keystone adapters. Mounting an ECF style jack or adapter is still pretty easy (see a video here), and the ECF style is an L-com standard, meaning the panel holes will all be the same.
A final consideration is water/dust contamination. If there is a chance that a jack may get wet or grimy, you should consider using sealed couplers. There are now many options for providing Ethernet connectivity in harsh environments, including jacks, cables, cable glands, and jack covers.Cable Termination Types
Once you have the jack mount-type down, it's time to consider what you are terminating to the jack. If you already have a terminated cable (a cable with a male RJ45 on it), a simple RJ45 coupler will do. But, if you have bare wires, you will need a 110 punch-down style jack. Of course, there are tool-free versions, but many installers prefer a good 110 punch tool to speed up the job. Whichever way you do it, make sure you have a jack that matches or exceeds the category rating of your cable, and if you use shielded twisted pair (STP) cables, you must install them properly.