Helvi Combi PC202K Инструкция по эксплуатации онлайн [5/64] 394384

NOISE

Noise is generated during the cutting process. The noise level depends on the cutting parameters used.

CAUTION!

Noise can damage hearing

Wear adequate hearing protection.

BURNS

The operator should be adequately protected during cutting operations. This should be routine practice.

CAUTION!

Do not point the torch jet at people or foreign bodies.

EMC

Before installing the plasma cutting unit, carry out an inspection of the surrounding area, observing

the following guidelines:

1-Make sure that there are no other power supply cables, control lines, telephone leads or other

equipment near the unit.

2-Make sure that there are no radio receivers or television appliances.

3-Make sure there are no computers or other control systems.

4-Make sure that there is no-one with a pacemaker or hearing aid in the area around the unit.

5-Check the immunity of any other equipment operating in the same environment. In certain cases

additional protective measures may be required.

Interference can be reduced in the following ways:

1-If there is interference in the power supply line, an E.M.C. lter should be inserted between the

mains and the unit.

2-The output cables of the unit should be shortened; these should be kept close together and stretched

along the ground.

3-All the panels of the unit should be correctly closed after carrying out maintenance.

GENERAL INFORMATION

PLASMA ARC AND BASIC PRINCIPLES FOR THE PERFORMANCE OF PLASMA CUTTING

√ Plasma is a gas that is heated to an extremely high temperature and ionised so that it becomes

a conductor of electricity.

√ This cutting procedure utilises the plasma to transfer the electric arc to the metal workpiece,

which is melted by the heatand then separated.

√ The torch uses compressed air from a single source, for both the plasma and cooling and pro-

tective gas.

√ The start of the cycle is determided by an arc, called the pilot arc, which is struck between the

mobile electode(negative polarity) ab dthe torch nozzle (positive polarity) due to the short circuit

between these two elements.

√ When the torch is brought into direct contact with the workpiece to be cut (connetcted to the

positive polarity of the power source) the pilot arc is transfered between the electrode and the

workpiece itself thus striking a plasma arc, also called cutting arc.

√ The duration of the pilot arc is set in the fatcory at 3 seconds; if the transfer has not been made

within this time, the cycle is automatically stopped except for the cooling air which is kept on.