Jasic EVO 2.0 EM-200CT, Operator'S Manual

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OPERATION - MMA
Before starting any welding activity ensure that you have suitable eye protection and
protective clothing as, welding rays, spatter, smoke and high temperatures produced in the
process may cause injury to personnel.
Also take the necessary steps to protect any persons within the welding area that may cause injury.
MMA welding
Arc force:
Arc force prevents the electrode sticking when welding. Arc force provides a temporary increase in
current when the arc is too short and helps maintain consistent excellent arc performance on a wide
range of electrodes. The Arc force value should be determined according to welding electrode diameter,
current setting, and process requirements.
High arc force settings lead to a crisper, higher penetration arc but with some spatter.
Lower arc force settings provide a smooth arc with lower spatter and a good weld seam formation, but
sometimes the arc is soft or the welding electrode can stick.
Hot start current: The EM - 200CT and EM - 250CT hot start is factory preset to 30A although adjustable in
the back ground settings from 0 ~ 60amps, see pages 25/26 for further information).
The hot start current is an increase in welding current at the start of the weld to give excellent arc ignition
and to avoid the electrode sticking. It also can reduce weld defects at the start of the weld.
The magnitude of hot start current is generally determined based on the type, specification, and welding
current of welding electrode.
During DC welding the heat on the positive and negative electrodes of the welding arc is different. When
welding using DC power supply, there are DCEN (DC electrode negative) and DCEP (DC electrode positive)
connections. The DCEN connection refers to the welding electrode connected to the negative electrode
of the power supply and the work piece connected to the positive electrode of the power supply.
In this mode the work piece receives more heat, resulting in high temperature, deep molten pool, easy
to weld through, suitable for welding thick parts. The DCEP connection refers to the welding electrode
connected to the positive power supply with the work piece connected to the negative power supply.
In this mode the work piece receives less heat, resulting in low temperature, shallow pool, and difficulty
in welding through. This is suitable for welding thin parts.
During welding:
PLEASE NOTE: The EM - 200CT and EM - 250CT units have preset anti - stick function by default.
In the welding process, if a short circuit occurs on the welding output for 2 seconds, the machine will
automatically enter anti
- stick mode. This means the welding current will automatically
drop to 20A to allow the short circuit to be cleared. When the short circuit is cleared the
welding current will automatically return to the set current.
Turn off the power supply after welding
On completion of any welding operating, the machine should be powered
down. The power switch is located on the rear panel of the machine
and should be set to the "off" position.
It maybe noted that for a short period of time that the machine fan
continues to run, this is quite normal and after a short time delay,
the control panel lights indicator will turn off and the fan will stop
indicating that the welder has now fully down.