Theory of operation, General description – Lincoln Electric MULTI-WELD SVM151-A User Manual

Page 32

GENERAL DESCRIPTION

The MULTI-WELD 350 Converter uses a single DC
input power source to provide up to 350 continuous
amps for positive polarity stick, wire processes, and
arc-air gouging. The machine converts higher volt-
age/lower current DC input power to lower
voltage/higher current DC output power with over 90%
efficiency. This DC output is controlled by Chopper
Technology to produce DC current for multi-purpose
welding applications.

INPUT POWER SOURCE,
CONTACTOR AND DC BUSS
POWER SUPPLY BOARD

The Multi-Weld 350 receives DC input power from an
80 VDC buss Multi-Source (recommended), although
other external DC sources such as the Lincoln Electric
DC-1000, DC-655, or DC-600 can be used if they pro-
duce 50 VDC or above.

The +50 VDC supply voltage is applied to the input
contactor via two large input diodes. The input contac-
tor establishes the electrical connection between the
Multi-Weld 350 and the power source when the
ON/OFF MODE switch is activated in either the con-
stant current (CC-stick) mode or the constant voltage
(CV-wire) mode.

A 40 VDC Buss Power Supply Board supplies 40 VDC
power to the Analog Control Power Supply Board,
which in turn feeds regulated voltages to a Weld
Control Board and 15 VDC to the Peripheral Board.
The Peripheral Board powers the input contactor coil
and the input indicator light on the front panel. The 40
VDC is also supplied to the Peripheral Board and is
passed on to the Weld Control Board.

E-2

THEORY OF OPERATION

MULTI-WELD 350