Heating elements in electrical devices are components that convert electrical energy into heat through the process of resistive (or Joule) heating.
When an electric current passes through a resistive material, it encounters resistance, which results in the generation of heat. These elements are integral to many household and industrial appliances. Here are some key points about heating elements:
Types of Heating Elements
Resistance Wire Heating Elements:
- Nichrome Wire: Made from nickel-chromium alloy, it's commonly used in toasters, hair dryers, and electric ovens.
- Kanthal Wire: An iron-chromium-aluminum alloy used in high-temperature applications.
PTC (Positive Temperature Coefficient) Heating Elements:
- Ceramic PTC Elements: These increase in resistance as they heat up, self-regulating to prevent overheating. Used in space heaters and car seat warmers.
Infrared Heaters:
- Quartz Heaters: Use quartz tubes to emit infrared radiation, often found in space heaters and industrial drying processes.
Film Heaters:
- Polyimide (Kapton) Heaters: Flexible and thin, these are used in applications requiring precise temperature control like electronics and medical devices.
Metal Heaters:
- Aluminum and Stainless Steel Heaters: Common in industrial applications for heating liquids and gases.
Applications
- Home Appliances: Toasters, ovens, electric kettles, and hair dryers.
- Industrial Equipment: Plastic molding machines, industrial ovens, and packaging equipment.
- HVAC Systems: Space heaters, underfloor heating, and heated car seats.
- Medical Devices: Incubators, sterilizers, and surgical equipment.
Working Principle
- Ohmic Heating: Electrical current flows through a resistive material, causing it to heat up.
- Heat Distribution: The generated heat is then transferred to the surrounding medium (air, liquid, or solid).
- Temperature Control: Often, thermostats or electronic controllers are used to regulate the temperature of the heating element.
Materials Used
- Nickel-Chromium (Nichrome): High resistance, stable at high temperatures.
- Iron-Chromium-Aluminum (Kanthal): Can operate at even higher temperatures than Nichrome.
- Ceramics: Used in PTC elements for their self-regulating properties.
- Carbon: Used in some high-power industrial applications.
Advantages
- Efficiency: Direct conversion of electrical energy to heat with minimal losses.
- Control: Easy to regulate and control the temperature.
- Versatility: Suitable for a wide range of applications and environments.
Disadvantages
- Cost: Some materials, like Nichrome, can be expensive.
- Wear and Tear: Heating elements can degrade over time, especially if not properly maintained.
- Safety: Risk of overheating and electrical hazards if not properly managed.
Overall, heating elements are crucial for various everyday applications and industrial processes, providing reliable and controllable heat generation.
ASB Heating ElementsInstallation:
Care must be taken to insure complete immersion of heated length of the heater at all times. The heated surface should never be in contact with any sludge.
In the case of flange and pipe-thread type heaters where a gasket seal is necessary, the gasket surface should be clean and dry before heater is seated. The electrical connections must be protected at all times from moisture or vapour; in hazardous locations, explosion-resistant covers are to be used.
The heaters should be periodically inspected for coatings and corrosion, and cleaned if necessary.
When melting solids by direct immersion, a surface vent should be provided to allow gases to escape. Operate the heater on voltage until melted material completely covers the heated area.
In an electroplating application, the metal surface or the heater is to be grounded. The heaters are not under any circumstance to be placed between the electrodes and the work.
Care must be taken to insure complete immersion of heated length of the heater at all times. The heated surface should never be in contact with any sludge.
In the case of flange and pipe-thread type heaters where a gasket seal is necessary, the gasket surface should be clean and dry before heater is seated. The electrical connections must be protected at all times from moisture or vapour; in hazardous locations, explosion-resistant covers are to be used.
The heaters should be periodically inspected for coatings and corrosion, and cleaned if necessary.
When melting solids by direct immersion, a surface vent should be provided to allow gases to escape. Operate the heater on voltage until melted material completely covers the heated area.
In an electroplating application, the metal surface or the heater is to be grounded. The heaters are not under any circumstance to be placed between the electrodes and the work.
General InformatiŠ¾n:
Immersion heaters with 115/120 volt or 230/240 volt elements can be connected in series for higher voltage operation except where uneven wattage is supplied on the respective elements.
Never bend the heating elements. If bending is necessary, check the factory.
Copper sheathed elements are generally used for water applications; steel sheathed elements are generally used for oil, wax, some alkaline, etc. applications. For other materials, check supplier for suggested sheath material.
Do not remove immersion heater from the tank while connected to the power supply.
Terminal are to be protected from drippings, spray, condensation and spilling. Use alloy bus bar or manganese nickel wire for electrical connections where temperatures might exceed 500°F. Insulated copper wire may be used where temperatures meet manufacturers recommendations. Protect terminal from flux when soldering heaters into tanks or containers.
ASBI-001 Installation & Maintenance Instruction for Liquid Immersion Heaters
You have selected an immersion heater made with top quality materials and expert workmanship. Properly installed and maintained these heaters will provide many years of trouble free service.
General: Temperature controls and temperature limiting controls are recommended for electric heaters. These will control the heating process and safeguard the heaters from over temperature that may cause damage to the heaters or the product being heated.
Installation:
1. Heater mounting must include adequate space for heater expansion.
2. Do not bend heating elements. The compacted magnesium oxide,inside the element sheath can be damaged which may lead to dielectric problems and/or premature heater failure.
3. Heater sheath must always be immersed in the liquid while energized. The heated surface should never come in contact with sludge.
4. All sealing surfaces must be clean and free from burrs or any surface irregularities that may prevent a proper seal.
5. Danger - Fire Hazard - Electric heaters can develop high temperatures and care should be taken to:
• prevent element sheath from contacting hazardous (combustible) gases or vapours. Hazardous location terminal boxes are available and have to be specified. Heaters with hazardous location terminal boxes have "ER" suffixes added to the Cat. No.
• avoid contact between combustible material and heater
• keep combustible material far enough away from the heater to prevent effects of heater high temperature
Wiring: This heater must be installed by qualified personnel to all local and national codes. Remove terminal cover and wire as shown on the wiring diagram. You must use appropriate size and temperature rated wire. Temperatures in the terminal box depend on the application and high temperature wire may be required. Do not connect heater to voltage higher than specified on the name plate. Wattage increase is proportional to the voltage ratio squared and excessive voltage will dramatically increase the heat output.
Operation:
1. Care must be taken to insure complete immersion of heated length.
2. Do not operate heaters under conditions that cause the sheath temperature from exceeding maximum recommended sheath temperatures; see Table 1.
3. Check recommended sheath material and liquid to be heated; see Table 1.
4. Unless otherwise specified terminal boxes are EEMAC 1 and should not be operated in environments that can cause electrical insulation breakdown. These environments include:
• oil, oil vapours or grease
• reactive or noxious gases
• water or water vapours
• corrosive liquid or gases
These contaminants can create electrical leakage's causing a shock hazard, heater damage and/ or premature heater failure. For protection in these environments specify moisture resistant terminal boxes. Heaters with moisture resistant terminal boxes have "MR" suffixes added to the Cat. No.
Immersion heaters with 115/120 volt or 230/240 volt elements can be connected in series for higher voltage operation except where uneven wattage is supplied on the respective elements.
Never bend the heating elements. If bending is necessary, check the factory.
Copper sheathed elements are generally used for water applications; steel sheathed elements are generally used for oil, wax, some alkaline, etc. applications. For other materials, check supplier for suggested sheath material.
Do not remove immersion heater from the tank while connected to the power supply.
Terminal are to be protected from drippings, spray, condensation and spilling. Use alloy bus bar or manganese nickel wire for electrical connections where temperatures might exceed 500°F. Insulated copper wire may be used where temperatures meet manufacturers recommendations. Protect terminal from flux when soldering heaters into tanks or containers.
ASBI-001 Installation & Maintenance Instruction for Liquid Immersion Heaters
You have selected an immersion heater made with top quality materials and expert workmanship. Properly installed and maintained these heaters will provide many years of trouble free service.
General: Temperature controls and temperature limiting controls are recommended for electric heaters. These will control the heating process and safeguard the heaters from over temperature that may cause damage to the heaters or the product being heated.
Installation:
1. Heater mounting must include adequate space for heater expansion.
2. Do not bend heating elements. The compacted magnesium oxide,inside the element sheath can be damaged which may lead to dielectric problems and/or premature heater failure.
3. Heater sheath must always be immersed in the liquid while energized. The heated surface should never come in contact with sludge.
4. All sealing surfaces must be clean and free from burrs or any surface irregularities that may prevent a proper seal.
5. Danger - Fire Hazard - Electric heaters can develop high temperatures and care should be taken to:
• prevent element sheath from contacting hazardous (combustible) gases or vapours. Hazardous location terminal boxes are available and have to be specified. Heaters with hazardous location terminal boxes have "ER" suffixes added to the Cat. No.
• avoid contact between combustible material and heater
• keep combustible material far enough away from the heater to prevent effects of heater high temperature
Wiring: This heater must be installed by qualified personnel to all local and national codes. Remove terminal cover and wire as shown on the wiring diagram. You must use appropriate size and temperature rated wire. Temperatures in the terminal box depend on the application and high temperature wire may be required. Do not connect heater to voltage higher than specified on the name plate. Wattage increase is proportional to the voltage ratio squared and excessive voltage will dramatically increase the heat output.
Operation:
1. Care must be taken to insure complete immersion of heated length.
2. Do not operate heaters under conditions that cause the sheath temperature from exceeding maximum recommended sheath temperatures; see Table 1.
3. Check recommended sheath material and liquid to be heated; see Table 1.
4. Unless otherwise specified terminal boxes are EEMAC 1 and should not be operated in environments that can cause electrical insulation breakdown. These environments include:
• oil, oil vapours or grease
• reactive or noxious gases
• water or water vapours
• corrosive liquid or gases
These contaminants can create electrical leakage's causing a shock hazard, heater damage and/ or premature heater failure. For protection in these environments specify moisture resistant terminal boxes. Heaters with moisture resistant terminal boxes have "MR" suffixes added to the Cat. No.
