2.3
Brief
Introduction
GRAND MIG adopts the latest Pulse Width Modulation (PWM) technology and the Insulated Gate
Bipolar Transistor (IGBT) power modules. It uses switching frequencies in the 20KHz-50KHz range so as
to replace the traditional line-frequency transformer type welding machines. Thus, machines are
characterized with excellent dynamic response, portability, small size, lightweight, low energy
consumption, etc.
MIG series of welding machines uses Mix gases as shielding gas to realize gas shielded welding, active
gas
（
Ar+O2
、
Ar+CO2
）
as shielded gas to realize MAG welding and inactive gas
（
Ar
）
as shielded gas to
realize MIG welding.
GRAND MIG has built-in automatic protection functions to protect the machines from over-voltage,
over-current and over-heat. If any one of the above problems happens, the alarm lamp on the front
panel will be lit and output current will be shut off automatically for the machine to protect itself and
prolong the equipment using life.
GRAND MIG Features:
1. Digital control system, real-time display the welding parameters;
2. High performance multifunction power source (MIG/MAG);
3. Waveform control, stable welding arc;
4. IGBT technology, low power consumption;
5. Rated Duty Cycle
：
GRAND MIG 351 MULTI SYN = 350A @ 60%(40°C)
GRAND MIG 501 MULTI SYN = 500A @ 60%(40°C)
GRAND MIG is suitable for all positions welding for various plates made of stainless steel, carbon steel,
alloyed steel etc. Applications applied to pipe installment, petrochemical, architecture equipment,
car repair, bicycle repair, handicraft and common steel fabrication.
The letter “X” stands for Duty Cycle, which is defined as the portion of the time a welding machine
can weld continuously with it’s rated output current within a certain time cycle (10 minutes).
The relation between the duty cycle “X” and the output welding current “I” is shown as the right
figure. If the welding machine is overheating, the IGBT over-heat protection sensing will send a signal
to the welding machine control unit to cut the output welding current OFF and light the over-heat
pilot lamp on the front panel. In that case, the machine should not be welding for 10-15 minutes to
cool down with the fanrunning. When operating the machine again, the welding output current or
the duty cycle should be reduced.
Relation of welding current and duty cycle
for
GRAND MIG 501 MULTI SYN
2.4
Duty cycle
and
Over-heat
Summary of Contents for GRAND MIG 351 MULTI SYN
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