Theory Of Operation; General Description; Input Line Voltage And Auxiliary Transformer - Lincoln Electric INVERTEC CV350-R Service Manual

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FIGURE E.1 – INPUT LINE VOLTAGE AND AUXILIARY TRANSFORMER

GENERAL DESCRIPTION

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The INVERTEC CV350-R is an inverter based
welding power source that offers constant voltage (CV)
welding and is rated at 350 amps at a 60% duty cycle.
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The INVERTEC CV350-R is designed special for
working together with Welding Robot by means of CAN
bus.
INPUT LINE VOLTAGE AND AUXILIARY
TRANSFORMER
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The INVERTEC CV350-R is connected with 380VAC,
50/60Hz three-phase power supply. The initial power is
applied to the CV-350R through a combination line
switch/circuit breaker located on the front of the
machine.
Two phases of the input voltage are applied to the
auxiliary transformer.
develops four different secondary voltages. The
220VAC is used to power the fan motor only.
NOTE:
The fan motor will start to run once the line

Theory of Operation

The auxiliary transformer
INVERTEC
switch is switched ON, and will not stop until it is
switched OFF.
There are three rectifiers located on the middle panel of
CV350-R which are used together with auxiliary
transformer to power related circuitry. The 36VAC is
rectified by the first rectifier and the resultant 50VDC is
applied to both the Control PC Board and the Switch
Board. The 12VAC is rectified by the second one and
applied to four-pin CAN bus connector. The 8VAC is
applied to Switch Board directly to power the circuitry
that checks the input voltage. Only one diode of the
third rectifier is used in motor drive control circuit.
The input voltage is rectified by Input Rectifier and the
resultant DC voltage is applied to the Switch Board.
NOTE:
Unshaded areas of Wiring Diagram are the
subject of discussion.
TM
CV350-R
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