Cebora PLASMA PROF 122 Manual De Instrucciones página 12

out to the point of needing replacement. When this occurs, it
lights the indicator lamp E
3) a further device cuts the machine off in case of malfunction
of a power component. This function is evidenced by the pilot
lamp R on .
To ensure the efficiency of these safety devices:
· Do not remove or short-circuit the safety devices.
· Use only original CEBORA replacement parts.
· Always replace any damaged parts of the machine or
torch with original CEBORA materials.
· Use only CEBORA torches, type P70 and P150.
·Do not use the machine uncovered. This is dangerous for
the operator and anyone else in the working area, and
prevents the machine from cooling properly.
2 OPERATION
Before using this machine, carefully read the CENELEC stand-
ards HD 407 and HD 433 also check insulation of cables.
Turn the device on using the knob A. The indicator lamp B will
light.
The motor-driven fan on the machine is thermostat-control-
led, and thus starts only when the generator needs to be
cooled.
In machines fitted with an emergency button, set the switch knob
to ON; when the indicator lamp lights, the machine status is
"ready". Moving the knob to START sets off the starting proce-
dure, which ends when the fan inside the machine starts. The
START position of the switch is not latched, thus when the knob
is released it returns to the ON position.
If the emergency button is pressed during operation, the machine
stops immediately and returns to the "ready" status.
After starting the machine, press the torch button briefly to open
the flow of compressed air.
For automatic torches, the torch button is the button or switch on
the pantograph connected to the wire, supplied attached to the
torch.
Make sure that, at this point, the pressure gauge O shows a
pressure reading of 5 bars (0.5 MPa); if not, adjust the pressure
using the knob M on the reducer, then lock the knob by pushing
it down.
Connect the work clamp to the workpiece, making sure that there
is a good electrical contact between the clamp and workpiece,
especially for painted or oxidated metal or pieces with insulated
coating.
Do not connect the clamp to the part of the material to be cut off.
Welding circuit should not be deliberately placed in direct or
indirect contact with protection wire if not in the workpiece.
If earthing is deliberately made on the workpiece by means of
protection wire, the connection must be as direct as possible, with
the wire having a section at least equal to the welding return current
wire and connected to the piece being worked on, in the same place
as the return wire, using the return wire terminal or a second earth
terminal closeby.
All possible precautions must be taken in order to avoid stray
currents.
Use the knob F to select the cutting current based on the
thickness to be cut, following these guidelines:
Aluminium: 3 ÷ 4 mm
8 ÷ 10 mm
15 ÷ 18 mm
22 ÷ 25 mm
12
(see fig. 2).
40 ÷ 50A
80 ÷ 90A
110 ÷ 120A
150A
Stainless teel up to
Mild steel up to 20 mm
up to 30 mm
up to 40 mm
The machines cutting current is fully adjustable, allowing the
operator to select the correct value according to the work
requirement.
Current values higher than those indicated do not interfere with
correct operation of the machine or torch, and at times can
improve the cutting quality because they reduce the production
of waste along the edges of the workpiece.
The hole diameter of the torch tip depends on the cutting current,
and must be as follows (also shown on the front panel of the
machine):
With 20/50A
40/90A
80/130A
120/150A
With cutting currents from 20 to 50 A and a standard or long tip
diam. 1.1 mm, it is possible to work on contact, thus with the tip
resting directly on the material to be cut.
In art. 946 PROF 122, the red pilot light S on the front panel
indicates that contact cutting is forbidden. This occurs when the
cutting voltage is set to greater than 50 A.
In other conditions, it is essential to use a spacer (dual-tip B or
spring type A, Fig. 8) to prevent the tip from coming into direct
contact with the workpiece. Keep the torch at a distance of
approximately 4 mm for use in automatic mode.
Press the torch button to light the pilot arc. If cutting does not
begin after 2 or 3 seconds, the pilot arc will go off, and thus the
button must be pressed again to light it.
When possible, the torch must be pulled towards the operator. It is
easier to pull than to push. Keep the torch upright while cutting.
When you have finished cutting and released the button, the air
continues to come out of the torch for approximately 1 minute
and 30 seconds, to allow the torch to cool. It is best to avoid turning the machine off before this time has passed.
If you need to make holes or begin cutting from the center of the
workpiece, the torch must be held at an angle and straightened
slowly, to prevent melted metal from being sprayed onto the tip
(see fig. 4). This must be done when si forano pieces more than
3 mm thick.
In automatic mode (see fig. 5), keep the tip 7/8 mm from the
workpiece; after making the hole, if possible, move it to a
distance of approximately 4 mm. Do not drill thicknesses greater
than 10/12 mm. For thicker pieces, the workpiece must be
perforated before cutting.
If you need to cut on the corners or in notches (Fig. 6), we
recommend that you use extended electrodes and tips. If circular
cutting is required, we recommend that you use the special
fig. 4
5 mm 40 ÷ 50A
80 ÷ 90A
110 ÷ 120A
tip ø 1.1 mm standard or long
tip ø 1.3 mm
tip ø 1.6 mm
tip ø 1.8 mm
150A
fig. 5