Flame Detection

The Preferred Flame Detection Method

PLASMA RESONANCE is a STACKMATCH Patented method of flame detection specifically designed for INSTANTANIOUS PILOT FLAME RECOGNITION and when unavoidable, to fail in the FAIL SAFE CONDITION.

Flare or Burner Pilot systems must normally operate under difficult and dirty ambient conditions.  To know that a pilot is functioning properly and that a stable flame exists at the Pilot nozzle is critical for safe Pilot operations.  Likewise, proper flame detection for a Pilot operating inside a vessel intended for ignition of Main Burner gas is crucial to the safety of the operation.  The speed of detection for both ignition and when flame failure has occurred is extremely important.  Unlike slow responding systems that depend on temperature settings for detection, PLASMA RESONANCE is a technology that provides for instantaneous Pilot Flame recognition, even under the worst of conditions.

To further understand the origins for the name given to this STACKMATCH patented method of flame detection, these definitions are offered:

Plasma: A hot electrically neutral, highly ionized gas composed of free electrons, ions and neutral particles.

Resonance: The natural excitation frequency exhibited by a burning gas confined within an open chamber.

To further understand the origins for the name given to this STACKMATCH patented method of flame detection, these definitions are offered:

Plasma: A hot electrically neutral, highly ionized gas composed of free electrons, ions and neutral particles.

Resonance: The natural excitation frequency exhibited by a burning gas confined within an open chamber.

Operating Principle

Gas becomes electrically conductive when its temperature is elevated to release the free electrons available within the gas composition.  This process, which describes the generation of an electron cloud that can move within the gas envelope, is better known as the Ionization Principle.

Ionization as a method of flame detection employing FIRE RODS or probes inserted into a flame has been available to the industry for many years.  This method determines the absence or presence of flame by monitoring the amount of current passing between the two conductive electrodes, each in contact with the flame and powered by an external power supply.  Unfortunately this method known as IONIZATION FLAME DETECTION is easily fooled when the electrode insulators become wet or dirty causing current to flow even when no flame is present.  This failure mode is well known throughout the industry and is further complicated as it occurs as a failure in the NON FAILSAFE CONDITION.  When other gas sources exist that depend solely on the failed Pilot for ignition a NON FAILSAFE CONDITION can quickly become catastrophic.

Even though PLASMA RESONANCE, the STACKMATCH method for Flame Detection, utilizes the same basic IONIZATION PRICIPAL, what is detected is not the amount of current but rather the current variations irregardless of current amounts.  The combustion process within a Pilot elevates the gas temperature releasing quantities of electrons with naturally occurring current variations that range in frequency between (500 to 5,000 Hz).  With the electronics tuned to this known PLASMA RESONANCE frequency, wet or dirty electrode isolators that cannot produce a frequency are of no consequence to PLASMA RESONANCE.  In addition, should the electrodes become shorted or the insulators so degraded that the signal is weakened to lower than acceptable levels, the system will indicate no Pilot flame even when the Pilot flame may still exist.  This type of failure in detection is in the FAILSAFE CONDITION.

Utilized in many different and difficult applications, and in daily operation at many locations throughout the world, PLASMA RESONANCE as a method of Pilot flame detection has, over the years, proven to be an effective and preferred state of the art technology.