LT 300 Gas-Air Premix Ignitors

Low Tension Gas / Electric Ignition with Flame Surveillance

LT300 Ignition Control System LT-gas-300-1 Ignition Control System

The Igniter control system has been designed to offer maximum reliability and flexibility. The Igniter uses only on low tension cable to transmit the spark and also to receive the flame on signal, giving maximum with less congestion of the equipment.

The Igniter Control System provides two functions
  • Flame Monitor
  • Spark Generator

The Igniter control system is designed to be used in conjunction with a single electrode gas-air mix Igniter rod. The Igniter Coil is mounted at the rear end of the Igniter Rod, and connections are via a 3 way plug and socket. The Igniter coil is fed from a pulsed generator which is switched by a Thyristor. This pulsed supply (140V Half Wave) is applied to the low tension winding of the coil, which in turn, generates the high tension spark.

  • Burner Ignition Systems
  • Permanent Pilot Duties
Signals required from management
  • Spark Signal (24VDC or Volt Free Contact)
  • Command to open Gas/Air Valves (Timed Process)

During the Spark On period, the ionisation detector rejects any signals from the spark generated, this being taken care of by a capacitor network, thus flame present detection can only take place after the spark is switched off and a flame on signal from the electrode is detected.

The Flame On signal is achieved by ionisation. When a gas flame is established, this permits the flow of positive ions between the electrode (Anode) and the Igniter body (Cathode). This gives a variable forward resistance. The Igniter Control System has a set resistance threshold and when this is reached; the relay in the control system is energised, indicated by orange Led Flame On. This change is displayed on a 0-10V analogue signal strength meter, which is incorporated into the unit to indicate when the gas air mix is correct.

ignitor-flame Specification
  • LT300 Igniter
  • Flame off time response 1 second fixed
  • Flame On output 1 relay changeover contacts rated 240VAC 1 amp
  • Short Circuit Fault Output 1 relay changeover rated 240VAC 1 Amp
  • Operating Temperature 0 - 85C
  • Spark Initiation 24VDC
  • Spark Initiation (Volt Free)
  • Power Requirements 115/230VAC 50/60Hz 20VA +10% -20%
  • 140VDC output to Igniter coil
  • Weight 1.5Kg

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LT300 Igniters

Gas Air Mixer Assembly

The Gas is supplied to the mixer and is prevented from entering the Igniter by 2 off solenoid valves. At the same time the air is supplied via a filter and regulator mounted on the ignition plate. This air is prevented from entering the Igniter by a single solenoid valve. When a voltage is applied to the solenoids the valves are opened allowing the gas and the air flow through to the mixer. The gas and air is metered entering the mixing chamber to give the correct gas air ratio for ignition. The flame is lit by a high tension spark at the tip of the pilot.

LT300s Gas/Air Pre Mix Igniter c2ag_200x57_3_lt300_1 igniter

This Igniter, of the gas-air mix design, produces a very hard stable gas flame and will light the main fuel all conditions of combustion air flow. It is possible to totally discriminate between the Igniter gas flame, and the main flame by incorporating our gas flame ionisation detection system. The igniter uses a high tension spark to ignite the primary mixture supplied from the gas/air mix valve complex. The pulse coil is directly mounted on the non firing end of the Igniter. The central ignition rod is also used to provide the ionisation signal. One stainless steel flexible hose is connected from the ignition plate to the Igniter. The Igniter is then fitted in a fixed position with the firing end behind the air stabiliser of the burner.

LT300XL Gas/Air Pre Mix Igniter

This igniter comprises an internal pre-mix pilot as described above, with an additional neat gas annulus providing additional heat input for special applications where a larger ignition flame or pilot is required.

LT300 Ignition Tester

lt300 ignition tester The Portable Ignition Tester enables simulation of the Ignition Spark and Manual Flame detection. This will give the engineer the ability to check the operation of the Igniter prior to installation into the burner. The Ignition system comes complete with Ignition Control System, aluminium carry case and 3M Ignition lead.

Dedicated LT300 Ignition Control System

ignitor-control The Credfeld Dedicated Ignition Control System comes supplied with an IP65 panel. The panel houses the Ignition Control System and a PLC, which controls the safe start up and shutdown of the Igniter. The panel is fitted with a start/stop and indicating lamps showing status of the Igniter. All necessary valve regulators and associated equipment are mounted to the Ignition Plate.