Tweco 250 Weldskill MIG - Manual (Page 26)

4-2 Manual No 0-5072 December , 2008
weldskill 250, 350 safe practices
Welding
Process
Welding
current range
Suggested
Filter Lens
GMAW 40 – 50A Shade 0
GMAW 50 – 250A Shade 
GMAW 250 – 300A Shade 2
GMAW 300 – 400A Shade 3
GMAW Over 400A Shade 4
Table 4- Filter lens size
Protective filter lenses are provided to reduce the
intensity of radiation entering the eye thus filtering out
harmful infrared, ultraviolet radiation and a percentage
of the visible light. Such filter lenses are incorporated
within welding handshields. To prevent damage to the
filter lenses from molten or hard particles an additional
hard clear glass or special plastic external cover lens
is provided. This cover lens should always be kept in
place and replaced before the damage impairs your
vision while welding.
NOTE
Recognised standards for recommended
practices for occupational eye protection
include AS/ANZ 336 and EN 75.
For maximum possible protection, the
use of full helmet equipment is recom-
mended.
The indicated filter lens shade numbers
are minimum. If any discomfort is felt,
higher shade numbers (i.e. darker filters)
should be used.