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To maintain the programmed temperature, a heater must compensate the considerable dispersions that happens at the tip and foot of the ...

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Standard modules deliver power using a reactive  method and this leads to significant stress in the components that shorten their average ...

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Taking care of micro nozzles


Form a thermoregulator point of view, micro nozzles are divided in two parts:
  • The head and foot of the nozzle, that need compensation for heavy heat losses.
  • The body that has only minimal heat dispersion
    This is the reason why nozzles have thinner coil around their central part, so as not to supply to much heat to a part of the nozzle that doesn't need it
Usually, standard modules don't care about the speed at which a nozzle is heated, with the risk of applying severe strains to it, both thermal and electrical. Sicem modules always output power in a controlled way and nozzles reach the desired temperature when it is really needed, avoiding harmful strains in the controlled components.

Even with a thinner coil around the body of the nozzle, the stem receives more power than what is needed: it's temperature will always too high.

The problem can get worse because:

  • An increase in the length of the nozzle
  • A high ratio length / diameter of the nozzle
This are problems that no thermoregulator can solve: overheating is the result of the shape of the nozzle, the alloys used to make it and the thickness of the coil

Overheating problems in the body of the nozzle are worse during the mould warm up phase. To reach the correct temperature at the tip, which is also where the thermocouple is usually applied , the controller must send a considerable amount of power to the nozzle to compensate for the heat exchange between the nozzle an it's surroundings. During this phase overheating can reach very dangerous levels, for the nozzle itself and for the materials contained within it.

Sicem modules use the µCARE function to solve micro nozzles heating problems. This function allows heaters to reach the operating temperature following a softer ramp, as can be seen in the right animation above.

The increased time needed to reach the programmed temperature does not constitute a problem because the µCARE function is synchronized with the DS-p function, that ensures that all nozzles reach the operating temperature at the same time.
Last Updated on Wednesday, 16 September 2009 15:04