Snap-On PLASMA50 Manual De Instrucciones página 5

9 CUTTING TROUBLE
1) Insufficient penetration
This may be due to:
• high speed. Always make sure that arc thoroughly pass-
es through the piece to be cut and that it is not tilted,
when going forward, by a percentage above 10 - 15°
(see picture 4). It is thus avoided to wear nozzle (see
picture 5) out.
• Excessive thickness of piece (see graph of cutting
speed and thickness)
• Work clamp H not properly in electric contact with piece
• Worn nozzle and electrode
• Too low cutting current.
When the unit does not completely cut through, nozzle is
clogged by slag.
2) Cutting arc switches off
This may be due to:
• worn nozzle, electrode or diffuser
• too high air pressure
• too low feed voltage
3) Tilted cutting
This may be due to :
a) too low air pressure with respect to the recommended
one
b) excessive burns on the end part of nozzle holder.
c) Excessive wear of consumable parts
4) Excessive wear of consumable parts
This may be due to :
a) too low air pressure with respect to the recommended
one
b) excessive burns on the end part of nozzle holder.
10 PRACTICAL RECOMMENDATIONS
• If the system air contains much humidity and oil it is
required to use a drying filter to avoid excessive oxidation
and wear of consumable parts, to avoid torch damage or
to reduce speed and quality of cutting.
• Impurities of air favor oxidation of electrode and nozzle
and make it difficult to start pilot arc. If this occurs, clean
the end part of electrode and inside the nozzle with fine
abrasive paper.
• Make sure that new electrode and nozzle are clean
and degreased.
• It is recommended to keep nozzle free from slag.
• Avoid using sharpened bodies thus avoiding damaging
the nozzle hole.
• Even if the unit is provided with an automatic device for
water discharge, working whenever air feed is closed, it is
recommended to check from time to time that no water
remains in trap I of reducer (picture 1).
• To avoid damage of torch and to prevent dangerous
situations always use genuine spare parts and con-
sumables.
11 TORCH MAINTENANCE
Always disconnect the unit before any repair of torch.
Replace wear parts (picture 7)
The parts subject to wear are electrode A, diffuser B and
nozzle C.
Either part may be only replaced after loosening nozzle
holder D.
Electrode A should be replaced when a 1/16"(1.5 mm)
deep crater is created in the middle (see picture 6).
ATTENTION! Do not make sudden stresses when
unscrewing the electrode, but gradually force so as to
have the thread unlocked.
required to be screwed in its housing and locked with-
out tightening.
Nozzle C should be replaced when its central hole is
damaged or enlarged with respect to the new part.
Use of worn electrode quickly wears out the nozzle.
Make sure that after replacing it, nozzle holder D is tight
enough.
ATTENTION! Nozzle holder D should be only screwed
on head when electrode A diffuser B and nozzle C
are assembled.
The absence of such parts jeopardizes the machine
working and particulary the operator's safety.
12 MAINTENANCE AND CONTROL
Any operation inside the power source must always be
carried out by qualified personnel.
Operations to be carried out inside the unit must be
effected after disconnecting the power cord.
It is required to clean from time to time the unit inside
and make it free from metal dust by means of com-
pressed air.
13 PRECAUTIONS TO TAKE AFTER A REPAIR
After making repairs, take care to re-order the cables so
that there is sure to be insulation between the primary
and secondary sides of the machine. Make sure that the
wires cannot come into contact with moving parts or
parts that heat during operation. Replace all clamps in
their original positions on the machine, to prevent a con-
nection between the primary and secondary circuits if a
conductor accidentally breaks or disconnects.
14 BASIC SAFETY PRECAUTIONS
WARNING: DISCONNECT POWER SOURCE BEFORE
DISASSEMBLY OF THE TORCH.
ELECTRIC SHOCK
Electric shock can kill. All electric shocks are
potentially fatal.
This plasma cutter requires high voltages for arc spark
starting (approx. 250 - 350 V). The following safety rules
must be therefore observed when using the unit:
• Do not touch live parts.
• Insulate yourself from the piece to be cut and from earth
by wearing insulating gloves and clothing
• Keep your clothing (gloves, shoes, hats, dresses) and
body dry
• Do not work in humid or wet areas
• Avoid touching or holding by hand the piece to be cut
• Always arrange for a proper insulation against electric
shock.
Should you work close to or in a dangerous area use
all possible precautions.
• If you feel even the slightest electric shock sensation,
This new electrode is
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