Cause Of Occurrence Of High-Pressure Discharge And Breakdown Phenomenon - JUKI PS900SB13090CKZ Instruction Manual

7-3. Cause of occurrence of high-pressure discharge and breakdown phenomenon

1) If the power supply of the laser equipment and the mains electricity differ in voltage or the power
supply which has different specifications (such as in the case of energizing a low-output tube with a
high-output power supply) is used, the rated voltage that the laser tube is able to withstand can be
exceeded, resulting in breakage of the laser tube.
2) In the case the entire cooling tube is not filled with water due to poor water cooling conditions, air
bubbles are formed. In such a case, the laser tube temperature will be increased excessively in the
part that has no cooling system. As a result, the glass portion of the laser tube can be broken in part
due to a change in glass property.
Recommended measure : ① Use the power supply provided by the manufacturer.
Requirement : Use soft water (distilled water or pure water) as the cooling water. Keep the water
temperature at 15 - 25 (°C) while carefully checking the temperature of the cooling
water continuously to prevent the excessive increase / decrease in temperature.
If the temperature excessively rises during the summer, in particular, immediately
change the cooling water with an appropriate one or stop the laser equipment to put
it at rest for a certain period of time. In a cold region, take care not to allow the cool-
ing water to freeze. It is important, in particular, to thoroughly discharge the cooling
water from the laser tube in order to prevent rupture of the laser tube due to freezing
of the cooling water after the laser equipment is stopped.
Special precaution : The user who uses the alternating current must ground the cooling water tank
② When you use the power supply provided by the manufacturer, check
that the laser equipment is connected to the waterproofing function.
Firstly, turn ON the cooling water system to circulate the water in the
laser tube according to the requirement "water is put from a lower
position and discharged from a higher position". Adjust the position of
the drain pipe so as to ensure that the cooling water tube is filled with
the cooling water with no air bubbles. Then, turn the power ON.
without exceptions.
Limit the flow rate of the cooling water to 8 - 13 (L / min). If not, the cooling
effect will be reduced to cause mode hopping. As a result, the spot will be
deformed to reduce the laser tube output. The condensate outlet (water outlet)
must be always immersed in water. If not, the cooling water tank water level
will be dropped below the full water lever every time the laser equipment is
turned ON and OFF.
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