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STEGO is - in the literal sense of the word - a high-profile supplier of enclosure heaters. With the new compact PTC enclosure heaters of the Loop series, we are sticking to proven virtues and concepts, but changing one essential element, the heating body. STEGO refers to the eye-catching heating body as Loop. The design was chosen with care and opens up a number of advantages for users beyond the usual performance of our control cabinet and enclosure heaters.

STEGO Loop Enclosure Heater - Heat Distribution

Heat distribution of enclosure heaters with the LOOP profile

your advantages at a glance

Heating body in Loop design
Shock and vibration proof
Heating better with Loop
Practical and user-friendly
Approvals, compliance, sustainability

HEating body In LOOP DESIGN 

Enclosure heaters are necessary, even if at first glance they seem trivial, electrotechnical components. They prevent the formation of condensation by counteracting temperature fluctuations in control cabinets, enclosures, and technical installation spaces. The typical standard design of a control cabinet heater is practical and rectangular. A successful representative in this spirit is the HG 140 heater.

Does the heating body cross-section necessarily have to be rectangular or square? 

We think not! The STEGO designers have found a superior alternative in the form of the Loop profile heating body.


Why Loop and what are the benefits of this design?

In a nutshell: tension release instead of pressing. The Loop profile enables an ingeniously simple and durable connection of heating body and heating element. Traditionally, the connection of these two assemblies is achieved by means of pressing. The process is approved and is rightly used. But there is a better way: with the Loop! 

The loop-shaped extruded aluminium profile enables a firm connection due to its inherent spring effect. Here, the elasticity of the aluminium is used in combination with the rounded geometry. During the installation process, the profile is initially placed with a specific tension and then allowed to expand. At this stage, the heating element is inserted into the designated position. The heating element is slightly larger in size compared to the gap in the assembly. Once the tension is released, the profile naturally rebounds and securely envelops the heating element. 

The Range at a Glance

Heaters with the new Loop profile. Click to go directly to the respective series. Please also note the practical CAD data download option in the product overview tables. 

  • Product series featuring the small Loop profile, output from 10 W to 50 W
    o    LTS 064
    o    LPS 164

  • Product series featuring the large Loop profile, output from 50 W to 150 W
    o    LT 065
    o    LTF 065
    o    LP 165







The touch-safe loop heaters are designed to be resistant to shocks and vibrations, meeting the standards required for railway applications. The VDE, a recognized testing institution, has certified the shock and vibration-proof capabilities of the Loop enclosure heaters from the LT 065, LTF 065 and LTS 064 series. These certifications are in accordance with the standards DIN EN 60068-2-27:2010-02 and DIN EN 60068-2-64:2009-04, in relation to the DIN EN IEC 61373:2011-04, cat. 1 B standard. All Loop series heaters with touch-safe design have successfully undergone and passed these rigorous tests.

Vibration proof beyond railway applications

Adhering to the railway stardards is a novelty for such a compact PTC heater. In addition to the obvious suitability for use in railways (trains, railcars, wagons) and their surroundings (control cabinets, housings and installation spaces in the area of control devices and track systems), this opens up further uses in applications subject to vibrations, e.g:  

  • Other mobile applications on land
  • Wind power and its energy storage environment
  • Machinery and equipment in the manufacturing industry

Loop heaters can thus replace the usual quite bulky vibration-proof heaters and be an elegant alternative where space is limited, yet they can withstand strong vibrations permanently and provide the required heating power reliably.


The STEGO Thermal Management experts use the advantages of the elastic and at the same time firm connection capabilities of the Loop profile to improve the very own task of our enclosure heaters: heating. After all, our customers are experts who require reliable thermal management that functions under all circumstances. At the top of the specifications for the Loop heaters were:  

  • Stronger and more compact connection of heating element and heating body
  • Increased resistance to thermal cycles 
  • Smaller frontal area for more space efficiency in the application
  • Optimised ratio of heat output to unit volume
  • Practical dimensioning of heating capacities

Heating element firmly in place

The Loop profile has been elaborately developed based on simulation results, the aim of which is to improve the chimney effect and thus maximise the heat output. The particularly positive-fit, firm and yet elastic connection provided by the Loop ensures that the heating element and body form a compact unit. This sustainably improves the heat transfer. In addition, a new insulating foil with particularly good thermal properties helps to optimise the heat output to the environment. 

Keyword - resistance to temperature cycles: The Loop also scores here and can cope with the load changes of alternating temperatures more easily than its classically pressed counterparts. This is because the elastic joining technology of the new enclosure heaters ensures the absence of micro-deformations that could potentially weaken the structure. 

The introduction of Loop technology goes hand in hand with automating the production of PTC heating elements, resulting in enhanced application safety. By improving process reliability, it eliminates the risk of PTC contamination. This minimizes potential errors and guarantees the highest level of quality assurance.


Practice-oriented space economy and heating capacity 

Practical space efficiency and heating performance were key considerations in the development of the new Loop technology. The aim was to surpass the advantages offered by the traditionally manufactured heaters in our product range. As a result, the unit width could be reduced by up to 40%, effectively saving valuable space on the DIN rail. In terms of dimensions, the heaters have a slightly greater depth, allowing them to extend further into the enclosure and thereby saving vertical space. The heating outputs now span from 10 W to 150 W, precisely meeting the evolving needs of users in thermal management.


50% faster installation with push-in clamps


The design of Loop heaters prioritizes user-friendliness and practicality. To ensure easy electrical connection, the units feature push-in clamps at their mounting ports. This allows for swift installation of both stranded wires (with ferrules) and rigid wires by simply pushing them into the terminals. Compared to traditional screw terminals, this saves an impressive 50% of labor time.

The ports are positioned as "front loaders" towards the front/bottom, considering the convenience of the installer. This arrangement enables effortless manual or automated connections during installation. Additionally, the obligatory clip for mounting the heaters on the 35 mm DIN rail is included as well.



Touch-safe: A Matter of Philosophy

Touch-safe variants of STEGO enclosure heaters have always been an integral part of our thermal management solutions. These touch-safe versions provide a secure means of protecting personnel from potential burns while commissioning and maintaining control cabinets. By incorporating a protective plastic coating, STEGO heaters ensure that their side surfaces do not exceed 80°C, thus allowing users to safely touch them. Moreover, the touch-safe feature guarantees protection against accidental contact, ensuring the property of protective insulation (IP20 / II). This commitment to occupational safety is a significant advantage that STEGO actively promotes as a leader in control cabinet heating.

Of course, loop heaters are also available in versions without touch-safe coating but with protective grounding (protection class I). The advantage of these "purist" versions is that users can witness the Loop heating body in all its technical finesse, with uninterrupted airflow.

An Integrated Solution

A notable feature of STEGO enclosure heaters is their practical and versatile design, specifically their wide-range voltage capability. These heaters can be connected to voltages ranging from AC/DC 120 to 240 V, allowing for a broad range of applications. This eliminates the need for enclosure builders to stock multiple types of heaters, thus reducing complexity and costs. The heaters utilize PTC thermistor technology, which inherently limits the temperature and eliminates the need for a temperature fuse. 

For added convenience, optional versions with integrated fixed thermostats are available. This helps simplify control cabinet setups by reducing complexity and eliminating the need for specifying and wiring an additional thermostat. Furthermore, STEGO offers customized product variants with adjusted voltages and switch-off/switch-on temperatures upon request, catering to specific requirements and preferences.


STEGO products are renowned for their certified safety, backed by extensive approvals and international conformity markings. This commitment extends to the new heaters in the Loop series. Accredited testing institutes like VDE and UL have granted their approvals, serving as proof to the safety and quality of our products. The presence of common national and supranational test marks, such as CE, UKCA, and EAC, further endorse STEGO products for use in international markets.

Our dedication to environmental responsibility is reflected in the RohS certificates of conformity, which comply with the European standard for limiting the use of hazardous substances in electrical and electronic products. The new Loop heaters also prioritize sustainability and recyclability. They facilitate residue-free dismantling, allowing for the valuable aluminum material of the heating body to be extracted and recycled according to its specific type.





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