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Chapter 5. Trial Operation and Adjustment
Ignition spark response (UV sensor)
WARNING
Ensure that the UV sensor does not detect ultraviolet rays other than those from the burner.
If the UV sensor responds to other ultraviolet radiation, fuel will continue to be supplied even if the
burner flame is off, potentially causing an explosion.
Before doing the spark response test, always make sure that all manual fuel valves are closed.
(1) Close the manual valves in the piping for the pilot and main burners.
(2) Begin operation and measure the flame voltage during the ignition trail
sequence to check for any effect from the ignition spark.
(3) If the spark has an effect, such as causing the FLAME LED to light up, refer to
the user's manual for the equipment and make adjustments in the following way.
•
Move the UV sensor or the ignition spark rod so that the spark does not affect
the flame voltage.
•
Attach a shield that prevents the spark's ultraviolet radiation from entering
the optical path of the UV sensor. Adjust so that the spark's effect on the
flame signal is 0.4 Vdc or less.
•
In the case of a solid-state power semi-terminal drive igniter (S7200AxxxGHx
or S720AxxxGHx), swap the polarity of the power to the igniter. When this
device is used in combination with a half-wave drive igniter, changing the
polarity of the power can prevent the the UV sensor's detection of the spark.
Handling Precautions
• Ensure that the UV sensor does not detect ultraviolet rays other than those
from the burner flame.
Sources of ultraviolet radiation (other than the burner flame) that can activate the
UV sensor include the following.
Examples:
Ultraviolet ray sources
1371 °C or hotter red-hot furnace wall (within 50 cm from wall)
Ignition transformer, welding arc spark
Gas laser
Sun lamp
Germicidal lamp, ultraviolet lamp, fluorescent lamp
Strong flashlight (towards UV phototube)
Gamma ray and X-ray
sources
X-ray analyzer, gamma ray analyzer/measurer
Electron microscope
X-ray machine
High-voltage vacuum switch
High-voltage capacitor
Radioactive isotope
Any other ultraviolet, gamma, or X-ray source
Содержание AUR890 Series
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