Cabinet Heaters

About Cabinet Heaters

Cabinet heaters are specialised heating devices engineered to provide frost protection and condensation control within electrical enclosures, control panels, switchgear cabinets, and telecommunications equipment housings. These compact heating units maintain stable internal temperatures in confined spaces where sensitive electronic components and instrumentation require protection from cold, damp conditions. Most cabinet heaters available from Tooled-Up utilise infrared heating technology, which emits radiant heat that directly warms surfaces and equipment rather than simply heating the surrounding air, making them exceptionally efficient for small enclosed volumes.

The primary purpose of these devices is preventing condensation formation on electrical components, circuit boards, and connection terminals—moisture that can lead to corrosion, short circuits, and equipment failure. By maintaining cabinet temperatures above the dew point, these heaters create a stable operating environment for PLCs (programmable logic controllers), variable speed drives, sensors, and other sensitive electronics in industrial, commercial, and outdoor installations. Cabinet heaters typically operate on standard 240v UK mains supply and are available in various wattage outputs, usually ranging from 40W for small control boxes to 150W or higher for larger enclosures or particularly cold environments.

Modern cabinet heaters feature compact designs suitable for DIN rail mounting or screw-fix installation, with many models incorporating thermostatic controls for automatic temperature regulation. This ensures energy-efficient operation whilst maintaining optimal conditions without manual intervention. The infrared heating elements used in quality cabinet heaters require no moving parts, resulting in silent operation, minimal maintenance requirements, and extended service life compared to fan-assisted heating alternatives.

Jargon Buster

• Infrared (IR) Heating: A radiant heating method that transfers thermal energy directly to objects and surfaces through electromagnetic radiation, without first warming the surrounding air. This technology proves significantly more efficient than convection heating in small, sealed enclosures where air circulation is limited.
• Thermostat Control: An automatic temperature regulation mechanism that monitors cabinet temperature and switches the heating element on and off to maintain a preset target temperature. This prevents overheating whilst minimising energy consumption and running costs.
• Wattage Rating: The measure of electrical power consumption and corresponding heat output capacity. Cabinet heaters typically range from 40W for small junction boxes to 150W or more for larger electrical cabinets, with the appropriate rating determined by enclosure volume and ambient conditions.
• IP Rating (Ingress Protection): A standardised classification indicating the degree of protection provided against ingress of solid particles (first digit) and liquids (second digit). Cabinet heaters for outdoor or harsh environments typically require IP54 minimum, with IP65 or higher for exposed installations.
• DIN Rail Mounting: A standardised metal rail system (35mm width) commonly found in electrical enclosures and control panels, allowing quick clip-on installation of cabinet heaters, circuit breakers, and other modular equipment without drilling or permanent fixings.
• Dew Point: The temperature at which air becomes saturated with moisture and condensation begins to form on surfaces. Cabinet heaters maintain internal temperatures above this critical threshold to prevent damaging moisture accumulation on electrical components.

Who Uses Cabinet Heaters?

Cabinet heaters serve essential roles across numerous trades and industries where electrical equipment protection is paramount:

• Electricians and electrical contractors installing outdoor distribution boards, control panels, and exposed electrical enclosures requiring frost and condensation protection
• Industrial maintenance engineers responsible for protecting PLCs, variable speed drives, and process control equipment in manufacturing environments
• Facilities managers overseeing building management systems, HVAC controls, and technical installations in commercial properties
• Agricultural engineers protecting automated feeding systems, irrigation controllers, and environmental monitoring equipment in unheated farm buildings
• Telecommunications technicians maintaining outdoor street cabinets, exchange equipment, and fibre broadband infrastructure
• Water and wastewater treatment operators safeguarding instrumentation, telemetry systems, and SCADA equipment in remote pumping stations
• Renewable energy installers protecting inverters, controllers, and monitoring equipment in solar and wind installations
• Security system installers ensuring CCTV recording equipment, access control panels, and alarm systems remain operational during cold weather
• Marine and offshore engineers protecting electrical systems and navigation equipment in harsh, salt-laden environments
• Transport infrastructure professionals maintaining railway signalling equipment, traffic light controllers, and automated gate systems

How to Choose the Right Cabinet Heaters

Calculate Heating Requirements: Measure your enclosure's internal dimensions (height × width × depth) to determine volume. As a general sizing guide, allow approximately 10-15 watts per cubic foot of cabinet space, though this varies depending on insulation quality, ambient temperature, and exposure to weather. Outdoor installations in unheated locations typically require higher wattage than indoor protected environments.

Environmental Conditions: Assess the installation location carefully. Outdoor cabinets, coastal environments, or dusty industrial settings require cabinet heaters with appropriate IP ratings—IP54 minimum for sheltered outdoor locations, IP65 for fully exposed installations subject to direct water spray or heavy dust. Indoor installations in clean, dry environments may only require IP20 or IP40 protection.

Mounting Configuration: Verify available mounting options within your cabinet. DIN rail mounting offers the quickest installation in standard electrical enclosures and allows easy repositioning if needed. Alternatively, screw-fix models with mounting brackets suit non-standard cabinets or installations where DIN rail isn't available. Always ensure adequate clearance—typically 100-150mm—around the heater for safe heat dissipation.

Thermostat Features: Cabinet heaters with integrated thermostatic control provide substantial energy savings compared to continuously-running models. Adjustable thermostats allow precise temperature setting, typically from 0°C to 40°C, enabling you to maintain optimal conditions without wasting electricity. For critical applications, consider models with visual temperature indicators or alarm outputs.

Power Supply Compatibility: Confirm the heater operates on standard 240v UK mains supply and check the current draw against your cabinet's available power capacity. Most cabinet heaters draw less than 1A at 240v, making them suitable for connection via terminal blocks or small contactors. Consider whether hard-wiring or a 13A plug connection better suits your installation requirements.

Safety Certifications: Select products meeting BS EN 60335 standards for household and similar electrical appliances, with appropriate CE marking. Quality brands like Draper and Sealey stocked at Tooled-Up.com provide certification documentation ensuring compliance with UK electrical safety regulations and HSE workplace equipment requirements.

Popular Accessories

• Digital thermostats and temperature controllers for precise multi-zone climate management in larger installations
• DIN rail clips, mounting brackets, and spacers for secure installation in various cabinet configurations
• Hygrometers and combined temperature-humidity monitors to verify optimal operating conditions and confirm condensation prevention
• Cable glands, cord grips, and weatherproof cable entries for professional power supply connections
• Timer switches and programmable controllers for scheduled heating cycles and energy management
• Ventilation grilles and axial cooling fans to provide balanced air circulation in larger enclosures
• Thermal insulation sheets and reflective barriers to improve cabinet thermal efficiency and reduce running costs
• Warning labels and identification tags for electrical safety compliance and maintenance documentation
• Electrical enclosures and junction boxes themselves requiring heating protection
• Temperature-activated switches and frost thermostats for backup protection systems

Safety Information

Installation Requirements: Cabinet heaters must be installed by competent persons or qualified electricians in accordance with BS 7671 IET Wiring Regulations (18th Edition). Always follow manufacturer installation instructions precisely, ensuring correct mounting orientation and adequate clearance distances. Maintain minimum 100-150mm clearance from combustible materials, cable bundles, and cabinet contents. Never obstruct the heater surface or restrict heat dissipation, as this creates fire risk and may damage equipment.

Electrical Connections: Ensure proper earthing and overcurrent protection are in place. Never exceed the cabinet's power supply capacity or modify heater electrical connections. Use appropriate cable sizes for the heater's current rating and ensure secure terminations. In outdoor or damp locations, use IP-rated cable glands and ensure all connections are protected from moisture ingress.

Operating Environment Matching: Verify the heater's IP rating matches your installation environment. Using insufficiently protected heaters in damp, dusty, or corrosive atmospheres creates serious safety hazards. Confirm the cabinet construction is suitable for the heater's operating temperature range and that adequate ventilation prevents excessive heat build-up.

Regular Inspection: Periodically inspect cabinet heaters for dust accumulation, physical damage, discolouration indicating overheating, or loose connections. Clean surfaces carefully with power isolated. Test thermostat operation regularly and replace faulty units immediately to prevent uncontrolled heating. Document inspections as part of your electrical maintenance records.

Regulatory Compliance: Ensure installations comply with HSE Electricity at Work Regulations 1989, particularly Regulation 16 concerning work on or near electrical equipment. For workplace installations, include cabinet heaters in periodic inspection and testing schedules. Maintain records demonstrating compliance with industry-specific safety standards applicable to your sector, whether food processing, chemical manufacturing, or hazardous area installations.

Frequently Asked Questions

What wattage cabinet heater do I need for my electrical enclosure?
Calculate your cabinet's internal volume in cubic feet (multiply length × width × height in inches, then divide by 1,728) and allow 10-15 watts per cubic foot as a starting point. For example, a 600mm × 400mm × 300mm cabinet (approximately 2.5 cubic feet) typically requires a 40-60W heater. However, outdoor installations, poorly insulated cabinets, or extremely cold environments may need 50-100% additional capacity. Tooled-Up stocks cabinet heaters from brands like Draper and Sealey with detailed sizing guidelines to help you select the appropriate model for your specific application.

Can cabinet heaters operate continuously without damage?
Quality infrared cabinet heaters are designed for continuous operation and can run 24/7 when properly installed with adequate clearances. Models with thermostatic control will cycle on and off automatically to maintain set temperatures, significantly extending heating element life whilst reducing energy consumption. The heating elements in professional cabinet heaters typically last 50,000+ hours under normal operating conditions. However, regular inspection and ensuring dust-free operation maximises service life and maintains efficiency.

Will a cabinet heater significantly increase my electricity costs?
Cabinet heaters are remarkably economical to run due to their low wattage and efficient infrared technology. A typical 60W cabinet heater operating continuously consumes just 1.44 kWh per day. At average UK electricity rates of approximately 30p per kWh, this equates to roughly 43p daily or £3 per week—a minimal cost for protecting potentially expensive electrical equipment from moisture damage. Models with thermostatic control reduce running costs further by only heating when temperatures drop below the set point.

Do cabinet heaters require specific IP ratings for outdoor installations?
Yes, outdoor electrical enclosures require cabinet heaters with appropriate ingress protection. For sheltered outdoor locations with indirect weather exposure, IP54 provides adequate protection against limited dust ingress and water splashing. Fully exposed installations subject to direct rainfall or heavy dust require IP65-rated heaters offering complete dust protection and resistance to water jets from any direction. Coastal or marine environments may benefit from IP66 or IP67 ratings for enhanced protection against salt spray and temporary immersion.

Can I install multiple cabinet heaters in one large enclosure?
Yes, larger electrical cabinets or control rooms often benefit from multiple strategically-positioned cabinet heaters to ensure even heat distribution and adequate capacity. When installing multiple units, calculate total wattage requirements based on cabinet volume and ensure your power supply can handle the combined load. Space heaters appropriately to avoid heat concentration in one area, and consider using a master thermostat to control all units simultaneously for consistent temperature management throughout the enclosure.