Theory of operation, Main inverter board – Lincoln Electric V155-S User Manual

Page 28

Advertising
background image

THEORY OF OPERATION

E-4

E-4

INVERTEC® V155-S

Retur

n

to

Section

TOC

Retur

n

to

Section

TOC

Retur

n

to

Section

TOC

Retur

n

to

Section

TOC

Retur

n

to

Master

TOC

Retur

n

to

Master

TOC

Retur

n

to

Master

TOC

Retur

n

to

Master

TOC

MAIN INVERTER BOARD

The Inverter Board includes the following circuits:

- Inverter Circuit: Through the use of Insulated Gate

Bipolar Transistors (IGBTʼs) the high voltage

(325VDC) input current is switched ON and OFF at a

frequency of 80KHz and fed to the primary of the

main transformer. The current is regulated via Pulse

Width Modulation (PWM). The width of each pulse is

determined by a ʻgateʼ signal from the Control Board.

(See IGBT Operation and Pulse Width Modulation

in this section).

- Main Transformer: The primary function of the main

transformer is to reduce the high voltge 80khz output

to the proper voltage for welding. It also serves to

insulate the operator from the input line. Additional

windings of the transformer provide both piamary and

secondary feeback signals to the PWM control circuit.

FIGURE E.4 — MAIN INVERTER BOARD

- Output Circuit: The output diodes and the output

choke rectify and filter the current from the secondary

of the main transformer to make it acceptable for

welding. The shunt provides the necessary current

feedback information to the Control Board.

Note: The shunt is shown off the board for clarity. It is

actually mounted on the Inverter Board.

CONTROL BOARD

W05X0708-1

(SCHEMATIC: X0708)

JP1

INPUT BOARD

W05X0701

(SCHEMATIC: X0701)

115/230Vac

50/60 Hz

ON/OFF SWITCH

5

2

N

L

G

WIRE TIE

4

1

BLUE

WHITE

WHITE

BLUE

WHITE

BLACK

AC2

AC1

PE

PWR2

PWR1

PWR4 PWR3

DC+

RED

DC-

BLACK

PCB CONNECTOR CAVITY NUMBERING SEQUENCE

(VIEWED FROM COMPONENT SIDE OF P.C. BOARD)

RIBBON CABLE

TWISTED CABLE

1

FAN

WHITE

RED

4

2

4 PINS

1

PE

RECONNECT

BOARD

W05X0408

(SCHEMATIC: X0408)

BLACK

JP4

BLUE

16

16 PINS

15

JP1

JP1

DC+

RED

DC-

BLACK

Y/G PE

INVERTER BOARD

W05X0519

(SCHEMATIC: X0519)

BLACK

RED

JP2

WHITE

W

HIT

E

P1

N1

BL

AC

K

RE

D

SHUNT

-

+

Advertising