Honeywell LG1093AC02 Turbine Flame Sensor

Honeywell LG1093AC02 Turbine Flame Sensor (replaces Honeywell LG1093AA04) – GE Part Number 261A1812P012.

Industrial power generation gas turbine installations demand the superior protection provided by the Honeywell UV Flame Monitoring System. The Honeywell flame monitor system detects the ultraviolet radiation emitted by a hydrocarbon flame and produces an output signal to indicate a flame or no-flame condition. This system has delivered proven performance on General Electric (and GE licensee) gas turbines for more than 35 years. Land-based and off-shore applications include power generation, pumping stations, shipboard power generation among other industrial uses. A variety of sensors types, amplifier types and sensor cable lengths are available.

Flame monitoring of a burner has comprised the use of thermocouples, expansion tubes, and radiation sensors. Due to the extremely high flame temperatures in process boilers, monitoring of boiler flames in large furnaces has been done mainly with remotely located radiation sensors or sonic microphone pickups, which detect the frequency of the flame.

Although the radiation sensor circumvents the problem of placing a sensor in the region of high flame temperature, it has shortcomings such as the inability to differentiate between flame radiation and radiation from the heated boiler or furnace wall regions. Thus, the flame may be extinguished and the flame detector will fail to respond. The fuel supply to the burners will continue to be discharged onto the hot furnace walls. This time lag between loss of flame and shut down of the fuel supply can cause an explosion.

There are specialized radiation sensors which sense ultraviolet radiation and others which generate signals corresponding to the amplitude of the high frequency flicker of the flame monitored. The sensors can distinguish between flame radiation and background radiation since both ultraviolet and flickering radiation find a source of excitation exclusively in the flame. The use of a flickering type radiation sensor produces an output signal that is continuously fluctuating. The fluctuation may be hard to distinguish, and the problem becomes one of accurate detection of this fluctuation.

Sensors are positioned to converge and the radiation magnitude received by the individual sensors is similar. A circuit means subtracts the output signals of the individual sensors of the pair, the steady and slowly varying components of flame radiation from the flame are effectively canceled leaving the rapidly varying difference signal for flame detection. The high frequency flame flickering is due to random pulses or burst of radiation from very localized sources in the flame, and there will always be a residual, varying component from the dual sensor system as long as the flame is present.

Features:

– High sensitivity with fast response time (0.1 sec typical)
– Amplifiers support multiple voltage requirements: 28 Vdc, 20-35 Vdc, and 115 Vac.
– Operating distances up to 1000 feet, sensor to amplifier.
– Available with Factory Mutual approval for explosive atmospheres.
– Available with European Directive CE mark for EMC 89/336/EEC, LVD 73/23/EEC and ATEX Explosive Atmosphere 94/9/EC.
– Qualified component on General Electric turbines.

Specifications:

– Geiger Mueller-type sensor phototube. Detects ultra-violet band and 1800 – 2600 angstroms. “Solar blind” and tolerant to black body radiation.
– Two-year shelf-line, 10,000 hours MTBF with over one billion operating hours.
– Mounting Interface: 3/4 inch internal NPT.
– Control Panel Connection: Teflon shielded cable with one inch external conduit thread.
– Operating Temperature: -40°F to +350°F.
– Window Pressure Rating: 150 psig at 400°F.
– Special Certifications:
– Factory Mutual: Explosion Proof Class I, Divisions 1 and 2, Groups B, C and D
– CE Mark: EMC Directive 89/336/EEC, ATEX Directive 94/9/EC, II 2G, EEx d IIA T3 or EEx d IIC T3 Models
AA34/35/36/44/45/46
– Cable Lengths:
– AA24/AA34: 16ft (4.9m)
– AA25/AA35: 42ft (12.8m)
– AA26/AA36: 61ft (18.6)