Medium Watt Density

Maxiwatt compressed cartridges

Cartridges with high watt density. They provide a great uniform distribution of heat, and are hermetically manufactured, which considerably increases the long life of the resistance as well as preventing the oxidation of the heating wire even at high temperatures. Over 25.000 measurements in high density cartridges available. High density Maxiwatt cartridges are manufactured from prime quality materials and undergoing the strictest safety controls, according with international standards.

  • Long-life
  • mediun temperatures
  • Maximum watts capacity 30w/cm2
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
  • Heat welding, 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 Model AC cartridge heaters are manufactured by means of compression for all their components, with the porpuse of lengthening their working life. The conductor wire is wound spirally the hard ceramic body into which the conductor lead is inserted, with no connection (sometimes, a connection may occur on the outside of the cartridge). Ceramic discs and heads are inserted to obtain insulation and protection. Everything is coated with checked pure magnesium oxide to ensure a total full cartridge. Later a process of compression and another of correction of the surface is carried out until the required measure is calibrated. Finally, a strict quality control is carried out to guarantee the best performance of the cartridge

Cartridge Heater
Ni-Cr 80/20 heating wire

The most important element for ensuring 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 insulating 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 thermal cartridge heater, maximum melting point, uniform and exact compression, perfect thermal conductivity, etc, so that the best insulation 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 insulating capacity of magnesium oxidebolts, 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]