ARC WELDING MACHINE POWER SOURCE

For hanging a welding arc it’s miles important to have the preferred cutting-edge inside the welding circuit. Depending upon the kind of present day required (ac or dc) it may be obtained from the subsequent assets.

A welding gadget or frequency changer (for ac welding gadget).
A dc generator of a welding rectifier (for dc welding).
The no load or open circuit voltage (OCV) need to be high enough to strike an arc, however not so high as to endanger the welding operator, as an instance, for a 2000A transformer the OCV should not be over 90 volts through for lower currents of say upto 600A OCV may be upto 100 volts.
With direct modern, the OCV should be at least 30 to 35 volts whilst with alternating contemporary it ought to no longer be decrease than 50 to 55 volts. An open welding arc can be sustained at 18 to 40 volts.
The minimal voltage for arc ignition is 25 volts which need to be attained within zero.05 second for the upkeep of a strong arc.
The power of the welding source should be sufficient to provide the desired welding modern-day.
It should be viable to tap the favored modern in the to be had limits either in countless steps 9stepless law) or in a big wide variety of discreet steps (stepped regulation).
The voltage of the electricity source should regulate itself rapidly with the trade in arc duration.
The brief-circuit cutting-edge need to be within limits of safety for power source windings.
It need to have output characteristics which fit the arc characteristics.
It must incorporate a low voltage deliver for the operation of auxiliary devices.
It should have a preferred obligation cycle and offer the specified volt-ampere traits.
It need to be light in weight, small in length, low in value, convenient in service and clean to hold.
Volt-Ampere Characteristics of a Welding Power Source

All welding electricity assets have two forms of running traits viz., static function and dynamic function. The static output function can be effortlessly hooked up through measuring the constant-nation output voltage and modern-day by using traditional technique of loading with the aid of variable resistors. Thus, a curve showing the output contemporary versus output voltage for a given strength supply constitutes its static characteristic.

The dynamic function of an arc welding power source is decided via recording the temporary versions occurring over a short periods in the welding modern and the arc voltage. Thus, it describes immediate versions happening over a brief c program languageperiod of time say a millisecond. Arc stability is determined by way of the combined interaction of the static and dynamic colt ampere   Welding transformers – Brouwer Metaal (V-I) traits of the welding system power source.

The intrinsic temporary nature of a welding arc is the principle motive for notable importance of the dynamic traits of an arc welding power source. Most welding arcs have constantly converting situations which might be mainly related to placing of the arc, metal transfer from the electrode to the weld pool, and arc extinction and reignition in the course of every half of cycle of ac welding.

The transient nature of the welding arc is also because of version in arc duration, arc temperature and electron emission function of the cathode.

The charge of change of voltage and current in arc welding system is so fast that the static volt-ampere feature of a strength supply can hardly be of any importance in predicting the dynamic feature of a welding arc. However, it’s miles best the static volt-ampere traits of a welding electricity source which might be supplied by way of the producer. Through they cannot supply the character of beha