3.6 RECOMMENDATIONS RESPECT TO CUTTING CYCLE.
The correct settings of the times indicated are essential for the equipment to work perfectly. Air must exist
before the arc is ignited, as if this does not exist, the torch head would be seriously deteriorated due to
the formation of the electric arc inside. The time that elapses between the appearance of air and the
ignition of the arc is what we have called preflow. We suggest the routine of slightly pressing the
pushbutton in order to get the air to come out without producing ignition. After checking the existence of
air we can now ignite the arc by pressing the pushbutton continuously.
The post-flow time is also very important with respect to the working life of the cutting torch. This time
delimits the degree of cooling of the torch after having carried out a cutting process. We do not
recommend reducing the value of this time unless work is only being carried out in the minimum cutting
position where 40 sec. post flow can be used.
The pilot arc time adjustment can be modified by prolonging it. Too long a pilot arc time is not suitable
as the life of the consumable elements decreases. However this time can be adapted to your needs.
3.7 INTERNAL PROTECTION ELEMENTS
The GAR CUT (V. Industrial) Plasma cutting equipment have the following internal protection elements:
- GENERAL SAFETY PROTECTION:
It forces the use of a tool to connect and disconnect the plasma torch (safety cap).
IF THE SAFETY CAP OF THE TORCH HAS NOT BEEN INSERTED, THE MACHINE WILL NOT BE
- PROTECTION AGAINST OVERHEATING. THERMAL PROTECTION (L3).
As soon as the transformer reaches a high temperature, a protection mechanism is activated which prevents
the cutting operation from being continued. This is indicated by means of the amber light L3 situated on the
front of the machine which will stay on when the torch pushbutton is pressed, as there is no cutting cycle.
- PROTECTION AGAINST ABSENCE OF PRESSURE IN PNEUMATIC CIRCUIT. (L2).
It is important for the air flow in the torch outlet to correspond to that given in table before, in order to
prevent deterioration caused by overheating of the torch. The machine has a pressurestat which prevents the
cutting operation if the intake pressure is above a limit value. This is indicated by a red pilot light L2 which will
stay on if the pressure is not correct. The pressurestat is on the inside of the equipment next to the regulating
filter. This pressurestat has an adjustment screw which enables the value of the minimum pressure to be
established (around 4.6 bar).
- PROTECTION AGAINST DIRECT CONTACTS IN THE PISTOL BODY.
In order to prevent dangerous voltages when carrying out work on the torch body (replacement of
consumable components, for example), the torch has a safety system (activated by the nozzle-holder) which
cancels the action of the pushbutton. However it must be borne in mind that the body of the torch must always
be handled with the MACHINE DISCONNECTED.
- PROTECTION AGAINST CUTTING WITHOUT THE EXISTENCE OF ELECTRICAL EARTH.
In order to prevent cutting without the existence of an electrical earth (cutting with the pilot arc) the
equipment has a cutting current detection system which times the pilot arc.
GAR CUT (V. INDUSTRIAL). Instructions Manual
WARNING !
OPERATIVE.
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