Low Watt Density.

Cartridges with low voltage charge are the most recommended for moderate heating up to 300ºC. Made with the best quality stainless steel tube that can be found, or with other material such as copper, brass or aluminium. Everything is perfectly calibrated, such as the exterior. A long-life ceramic piece is inserted into the tube and stands up to every continuous temperature variation, together with the best possible thermal conductivity, as the piece is in contact with the wall of the tube, giving a perfect distribution of the heat.

  • Economical
  • Uniform temperature
  • Variety of terminations
Cartridge Heater


They are able to resist the toughest working conditions, such as vibration, moisture, fluid, spills, frequent expansion and where temperatures of between 400ºC and 750ºC are required, or temperatures within a limited space.


  • Molds
  • Smelting of materials
  • Heating of fluids
  • Welding heating, etc

The unique Maxiwatt manufacturing system, together with its electronic system, makes it possible to separate the spirals, guaranteeing the same temperature for the whole perimeter and length of the cartridge. Therefore, an uniform and long lasting temperature is obtained

Cartridge Heater

Maxiwatt AC Model The heater wire is inside the ceramic piece and is of first class quality. The nickel-chromium heating wire is the most recommended in the manufacturing of cartridge heaters due to its high degree of tolerance to high temperatures. Coated with checked magnesium oxide, covering the whole inside of the cartridge heater. Obtaining, a perfect conductivity between the heating wire and the heater

Cartridge Heater
Ni-Cr 80/20 heating wire

The most important element to ensure the long life of the cartridge heater is the heating wire used in its manufacturing. Maxiwatt uses the best to be found anywhere in the market. After extensive research and years of experience it has been shown that a heating wire made of Ni-Cr 80/20 is both efficient and resistant to the formation of metallic coating brought out by oxidation. As the austenitil combination of nickel and chromium lacks iron, it is the most recommended for the heating wire.

Total insulation

Magnesium oxide is used for insulation, and is the most suitable for isolating the heating wire and the conductor lead against the current of the sheath of the cartridge. When the space between the heating wire and the protecting sheath is too short, an insulator is required, this should be composed of the best qualities: purity, high degree of thermic cartridge heater, maximum melting point, uniform and exact compression, perfect thermal conductivity, etc, so that the best isolation is obtained.

Control of the working temperature is essential. It must never exceed the working limits of the cartridge. It is very important to store the cartridge in a dry space because magnesium oxide is very hygroscopic. Just a few drops of water particles are enough to weaken considerably the isolating capacity of magnesium oxide bolts, opposite outputs, etc. The different types of connection are shown on protections section.

Conductor lead

For the induction of electricity a nickel cable (sheathed by fiberglass) is used. It is coated with silicone and fire-proof glazing. The cable wires are turned. Sometimes, the charge of the cartridge prevents the use of this type of connection. Finally, special procedures are used: threaded outputs with bolts, opposite outputs, etc. The different types of connection are shown on protections section

Stainless steel 321: cover

The stainless steel 321 cover provides the highest quality to the manufacture of cartridge heaters. The materials which can be used in their manufacture are limited due to the strain caused by constant expansion due to the cooling and heating of the cartridge heater, the lack of a metal cover, which causes oxidation, and abrasive action. Stainless steel has been shown to be the most suitable material for the construction of cartridge heaters

Technical Key

Sheath material
Stainless steel 1.4541
Heating conductor material
NiCr 8020
Max. Sheath temperature
750 ºC / 1380 ºF
Max. Voltage
480 V
Wattage tolerance*
+5% -10%
Hight voltage resistance*
1500V AC at > 24 V operation voltage
500V at <= 24 V operation voltage
Insulation resistance*
>= 5 MW at 500 V DC
Leakage current*
<= 0.5 mA at 253 V AC
Length tolerance
A 1.5% min A 1mm
Standard diameter tolerance
metric -0.02 / -0.06 mm
inch: A 0.79 mils [A 0.02 mm]