Set up, wired and ready to go
While the final assembly and commissioning of a control cabinet may seem straightforward, the reality is often more complex. In the preliminary phase, precise design and planning of components are essential, along with strict adherence to applicable standards and regulations. Integrated electrical and electronic components—such as fuses, contactors, relays, and controllers—combine to form a sophisticated switch cabinet unit that serves as the core of an electrical system or a complete production facility.
Devices in the control cabinet
Much like the human heart, the control cabinet comprises a wide array of individual components that must operate in harmony and, ideally, with minimal downtime over extended periods. High-quality electronics are indispensable in this context. Equally critical are the enclosures that shield these electronics from external influences—features such as flame-retardant materials, secure locking mechanisms for standard rails, varied module widths, and both flat and high-profile designs. These are among the many attributes that DIN rail enclosure manufacturers must consider to accommodate a broad spectrum of customer requirements.
Different types of enclosures for the top-hat rail
Each control cabinet is typically customised to suit a specific application. However, to facilitate streamlined planning and efficient installation, established standards are incorporated into the design and development of top-hat rail enclosures. These standards are outlined in greater detail below.
There are DIN rail enclosures, which are primarily designed for front wiring, as well as enclosures for side cable outlets (e.g., the new RAILTEC BP) and profile enclosures (RAILTEC Support). Based on their design, all three housing types are mainly used in open control cabinets or small distribution boards where the installation depth is not a significant factor and the devices or live components do not require touch protection covers (refer to the section ‘Conductor separation for enclosures according to DIN 43880 and small building distributors’), e.g. as devices for
- Switchgear
- measuring and monitoring relays
- technical machinery and equipment
- building automation
- communication technology and much more.
Enclosures intended for use in so-called ‘open’ control cabinets offer considerable flexibility in depth; however, their height should not exceed 90 mm. This limitation arises from two key factors: many circuit boards adhere to applicable standards, which are more cost-effective manufacturing processes, and sufficient space must be maintained for installation and removal when devices are closely positioned within the cabinet. These enclosures feature a rear mounting bracket equipped with snap hooks designed for DIN rail installation. This mechanism permits vertical movement of the enclosure—swinging up and down from the pre-mounted rail. In the absence of adequate clearance above or the possibility of lateral access, installation becomes significantly more challenging.
Conductor separation for enclosures according to DIN 43880 and small building distributors
The RAILTEC B and RAILTEC C enclosure series from OKW are ideal for this application, although both top-hat rail enclosures are also popular in open control cabinets, depending on the device characteristics. The module widths are based on DIN 43880, ranging from 1 module (width 17.5 mm) to 12 modules (width 210 mm), with depths up to 45 mm and maximum heights of 90 mm. After final assembly of all electrical devices in the small distribution board, everything is sealed with a protective cover, leaving only the operating elements and status indicators visible (the cover has standardised cut-outs for this purpose). All connections and cabling are securely enclosed behind the cover, rendering them inaccessible to unauthorised individuals.
Installation on standard mounting rails compliant with DIN EN 60715
RAILTEC enclosures are designed for snap-in mounting on the most commonly used DIN rails in accordance with DIN EN 60715 – 7.5 mm or 15 mm (2 different versions, each with the same depth) with a height of 35 mm. In addition, the RAILTEC B enclosure series offers the option of mounting the devices directly on the wall or on the rear panel of the control cabinet using appropriate wall brackets.
Different connection techniques
Various connection techniques are available (see figure below), and their application depends on the available space within the control cabinet and its design. In distributors requiring the protective covers referenced above, wiring space is significantly restricted. Cable routing is limited to entry from the top and bottom, with cable lengths needing to be kept short. It is important to note that cables and plugs must be disconnected and reconnected during servicing, and insufficient cable length presents a clear issue in this context.
RAILTEC C & B: Conductor outlet for enclosures according to DIN 43880
RAILTEC BP: Double-sided bent conductor outlet
RAILTEC SUPPORT: Conductor outlet for profile enclosures
Cable Connections
There are basically two ways to connect the supply lines to the device: a fixed connection via screw/spring connections directly on the circuit board or via plug-in connections. In the latter case, the cable conductors are connected to a plug, and the counterpart is connected to the circuit board.
Heat dissipation
Devices and components always release heat into the environment during operation. Since plastic insulates rather than dissipates heat, and since enclosures are usually arranged close together to save space, meaning that heat cannot escape from the sides, enclosures with ventilation slots are often used. For this reason, the RAILTEC product range also includes a wide variety of versions with integrated ventilation slots or variable configuration options.
NEW: RAILTEC BP
The new RAILTEC BP M22 is a versatile electronics enclosure for mounting on EN 60715 TH35 DIN rails. It is ideal for measuring/control devices and its dimensions are based on industrial standard sizes.
RAILTEC BP M22 is available in three different side panel configurations: closed, single-sided with ventilation slots and double-sided with ventilation slots for increased heat dissipation. The panel variant is characterised by particularly simple and flexible assembly and efficient, screwless enclosure mounting.
A transparent cover is also available, which protects the front and the integrated operating/display elements, interfaces, etc., while ensuring a clear view. The protective cover can be swivelled upwards or downwards as required.
Leave Your Feedback