DIN Rail Enclosure Installation Guide

When working with electronic installations, especially in industrial control, automation and networking applications, you will undoubtedly come across the DIN rail in your journey. These rails — named from the acronym for “Deutsches Institut für Normung” or “German Institute of Standards” — are the metal rails used to mount electronic components in control cabinets, junction boxes or electronic enclosures. You can think of them as the backbone of complex electronic setups, as they are the components that house circuit breakers, contactors, terminal blocks, transformers, relays and other control equipment to the rack within a cabinet.

The fact that DIN rails are made to an industry standard, which is now adopted globally, allows them to be compatible with many different electronic components. As such, you can be sure that your DIN rail’s terminal blocks or circuit breakers will fit regardless of the manufacturer. This standard also allows us to produce DIN rail enclosures (sometimes referred to as “top hat rail enclosures”) that are compatible with the rails you already own or plan to use in your next project. Polycase is an excellent resource for finding easy-to-install rail enclosures for many applications.

We recommend implementing these kinds of mounting rails and enclosures in any environment where you don’t want to fuss with panel mounting, or for applications such as control panels when you want a central location for all of your equipment. What’s more, DIN rails can help you save space while also reducing labor time and cost, as they allow engineers to easily and quickly attach interchangeable components to the rail. At a glance, these rails simplify and standardize setups so that you can effortlessly work with parts and products from many different manufacturers.

In this guide, we’ll cover the different DIN rail enclosure options we offer at Polycase, as well as information on how to install your electronic enclosures onto DIN rails and how to use enclosures that house DIN rails. While a good majority of DIN rail jobs are hyper-specific to the user, there are some basics that apply to most projects to help you get started. We will also help you determine which type of enclosure is appropriate for your unique DIN rail needs, as you should be well aware of materials and how they perform in certain environments.

Din Rail Enclosures: Types and Options

We offer two primary types of DIN rail products at Polycase: DIN rail kits to install inside enclosures and enclosures that mount onto DIN rails. Be sure that you understand the difference before you embark on your DIN rail endeavor.

• DIN RAIL KITS FOR USE INSIDE ENCLOSURES: DR SERIES —The most common type of DIN rail mount enclosure is the style that houses DIN rails. We sell pre-fitted DIN Rail Kits for these applications. They are designed to fit our WH, WQ and YH/YQ series NEMA enclosures. These types of DIN rails are made of slotted steel with a zinc-plated finish. The custom-cut DIN rail kit includes two screws for installation.

• ENCLOSURES THAT MOUNT ONTO DIN RAILS: EK SERIES —The second type of DIN rail enclosure we offer is an enclosure designed to mount directly onto DIN rails. The EK Series Din Rail Mount Enclosure fits DIN-35 rails (35mm rails) and has one side with a DIN clip and one smooth side for simple label application. It’s made from flame-retardant ABS so it can be used safely in a range of different indoor environments. The product includes the base, cover, DIN rail clip and four enclosure screws.

If your goal is simply to find an enclosure that makes for very easy installation of your existing DIN rails, we have a good option for you. Many of our customers prefer the SK Series Enclosure with Knockouts when working with DIN rails because of the centered mounting bosses on the base of the enclosure, which help when installing the DIN rail. These enclosures are made of fiberglass reinforced polycarbonate and are weatherproof and waterproof. They are made in Germany by Spelsberg, one of the leading manufacturers of electrical equipment.

Even though we do not currently offer DIN rail kits cut to fit our SK Series, we would suggest these cases for DIN rail applications because of the centralized mounting bosses that make it especially easy to assemble DIN rail within the enclosure. SK Series enclosures also have knockouts, easily removable with a screwdriver, that allow for smooth installation of cables or wiring without needing additional customization.

Things to Know Before You Buy DIN Enclosures

Below, we’ve outlined how to install the Polycase DR Series and EK Series DIN enclosures, but there are a few things you should take into consideration before you start installing to ensure that your setup is safe, up to code and protected from damage.

• Keeping Your Setup Up to Code — In the U.S., if you’re working with electric motors, you will need to make sure that your DIN enclosures are UL listed. Our enclosures that house the DR Series DIN rails, as well as our ventilation accessories, are listed to satisfy this standard. You may also need materials that are fire retardant or weatherproof depending on the environment and codes.
• Buy the Right Enclosure for Your Environment — Weatherproof NEMA enclosures can be ordered for outdoor applications or environments that are particularly wet, dirty or demanding. Do not install an enclosure that’s not NEMA rated outdoors, as this could cause corrosion and damage to the expensive parts and delicate wire connections housed inside the enclosure.
• Choose the Right Enclosure Material — Take into account the metal of your DIN rail before choosing an enclosure. We generally recommend polycarbonate enclosures for these applications, as they can safely pair with any DIN rail material. If polycarbonate doesn’t satisfy your needs, be sure to use the same metal for your rail and enclosure.
• Know Your DIN Rail Size — As a general rule, 35-millimeter wide DIN rail (TS-35 or DIN-35) is the standard , but you will find 32- and 15-millimeter-wide options. Our DIN rail kits for mounting inside enclosures adhere to the 35-millimeter standard and our EK-50 enclosures fit this size. The DR Series DIN rail kits are made from 1-millimeter thick slotted steel to comply with the EN 60715 standard.
• Think About Mounting — Of course, if your enclosure doesn’t meet your mounting needs, it won’t be very useful to you. If the EK-50 enclosure doesn’t work for your specific project, you can make any enclosure DIN rail mountable using a Phoenix Contact Din Rail Clip or similar products. You can also shop our enclosure accessories for mounting kits.

Which One Do You Need?

The primary considerations when choosing a DIN rail enclosure are:

• Application — Do you need to install the rail inside the enclosure (DR Series) or do you need an enclosure that mounts onto a DIN rail (EK-50)? You can use a DIN rail assembly in applications where you need to house a power supply, DC/DC converter, timer, surge suppression device, Ethernet interface, programmable logic controller, circuit breaker, terminal strips and more. Your components will help you determine which size and style of rail enclosure to choose.

• Environment — You will want to make sure that you’re choosing enclosures that are made to withstand the specific environment where it will be installed. All Polycase enclosures that house DR Series kits are designed to meet NEMA 4X specifications, so they’re ideal for both harsh indoor and outdoor environments. In the U.S., DIN rail systems that control electric motors must comply with UL standards, specifically the 508 standard. Our enclosures are UL listed and satisfy this requirement.

• Size — Of course, the size of the enclosure depends entirely on what you need to house and the components that will go inside the enclosure. A large terminal strip with dozens of connectors will take up a lot more room, so be sure to carefully consider the size requirements of your enclosure. Remember, too, that it’s important to leave room in the enclosure for electricians to access the internal components.

• Material — The pairing of material between the rail, enclosure, cabinet and other components could affect performance, so it’s important to choose the right material. Aluminum enclosures should be paired with aluminum DIN rails, etc., as dissimilar materials could cause corrosion and electrical grounding problems. Material should also be considered for strength and environment. Polycarbonate enclosures are always a good choice because they can be paired with any DIN rail material.
• Ventilation — Another important facet of these types of enclosures is the ability to ventilate and control heat transfer through holes and other venting options. We also offer vent plugs and other venting accessories that help with heat dissipation. These accessories are UL listed, so they won’t compromise compliance if you need them to help with venting.

The Next Step in Choosing Your Enclosure

If you already know which enclosure will best suit your project, you can order it now at Polycase. We offer both plastic and metal din rail enclosure styles. Be sure to take advantage of volume discounts if you need multiple enclosures or kits to complete your job. If you don’t see what you’re looking for, be sure to contact us, and we can work with you to try to customize one of our enclosures to fit your needs. Or, you can self-quote a customized enclosure using our online Quick Quote tool. We are always available to assist you with finding the perfect DIN rail products.

How to Install DR Series DIN Rail Kits

Polycase DR Series DIN rail kits include a zinc-plated steel DIN rail plus two screws for assembly. Each rail is custom-cut to length to fit its designated WH, WQ or YH/YQ NEMA enclosure. Note that, because the steel is slotted, we take special care in where the cuts are made to ensure that it aligns for the correct mounting configuration inside the case.

DIN rails can be assembled lengthwise or widthwise inside the base of the enclosures. The DIN rails are secured down into the base of the enclosure via the screws provided, to the mounting bosses. Once secured in place with screws, you can start assembling your components to the DIN rail.

How to Install EK-50 Series DIN Rail Enclosures

The EK-50 enclosure box and DIN rail clip come as two separate pieces. Once your components are assembled within the box, you can connect the box to the DIN rail via the provided clip. You will first affix the clip to the DIN rail in your desired location. Next, the box portion simply snaps right onto the clip. It can be easily removed from the clip, as well, by snapping it off the clip, which is helpful if you need to switch out the electronic components within the case, etc. However, the clip does include two screw holes that provide the option to secure the box and clip firmly in place if you do not want the clip removed from its location along the DIN rail.

Contact Us for More Information

If you aren’t sure whether or not any of these enclosures will work with your specific project, or if you need more in-depth information on installation, get in touch with us, and we’ll do our best to assist. Polycase is a leader in CNC machining and enclosure manufacturing, so we’re always a great place to start if you need prefab or custom enclosures.