R
EQUIRED
E
QUIPMENT
T
RANSPORTATION
AND
I
NSTALLATION
C
HAPTER
3
3-2
•
Use an engine generator with a damper winding that has a capacity of more than twice the rated input
(kVA) of the welding power source.
Generally, the recovery time of the engine generator's voltage for load change is slower than that of the
commercial power source. If the engine generator does not have sufficient capacity, sudden current
change such as arc start will occur and this may result in an abnormal decrease in output current or arc
loss.
•
Be sure to use a single welding power source with a single engine generator. If more than two welding
power sources are combined, output voltage will become unstable with a likely result of arc loss.
Use the auxiliary power of engine welder with an improved voltage waveform.
Some engine welders have poor electricity that may cause product damage on the welding power source.
3.1.2
Ventilation equipment/partial exhaust facility
This section explains the ventilation equipment and partial exhaust facility in welding work area.
3.1.2.1
Ventilation equipment
When welding is required in tank, boiler, reaction tower, or hold of a ship, closed space, or any other
places of poor ventilation, ensure to provide ventilation equipment.
Condition of ventilation equipment:
Oxygen concentration of 18 % or more must be maintained in the welding work area.
3.1.2.2
Partial exhaust facility
To prevent any health damage due to poisonous gas or particle substances (fume) emitted in the welding
operation, provide partial exhaust facility.
• Gas of larger gravity than that of oxygen, such as carbon dioxide gas or argon gas,
retains at the bottom part.
To prevent anoxia due to the retention gas, provide ventilation equipment.
• When it is difficult to provide ventilation equipment or the ventilation equipment does
not give sufficient performance, ensure to use respiratory protective equipment.
• Periodically inspect the ventilation equipment to ensure correct and proper
performance of ventilation.
• When it is difficult to provide a partial exhaust facility or the ventilation or exhaust
facility does not give sufficient performance, ensure to use the respiratory protective
equipment.
