Control Board - Tft Ui & Hf Board - Lincoln Electric INVERTEC 300 TP Service Manual

CONTROL BOARD AND TFT UI
BOARD
The Control Board managing all the functions of the
machine, a microprocessor is present on it to make the
correct operations. The Control Board receives signals
from different area of the machine, power supply from
Aux. Power Supply board and selecting parameters
from the User Interface to create the reference signal
for the inverter.
Control Board and User interface communicate via
serial bus.
The Control Board supplies power for the User
Interface Board and supplies signals to the User
Interface to show set and actual current values, error
codes and pre-set values. It also receives signals from
the TIG torch connector (pin 1 & 2) or remote
connector (pin D & E) to initiate the welding output.
The remote control signals (Pins A, B & C) are also fed
CONTROL BOARD – TFT UI & HF BOARD
into the Control Board from the 6 pins connector
located on the front of the machine.
HF BOARD AND HF TRANSFORMER
The HF Board generates a set of 97Hz pulses
of about 1000V. These pulses are applied to the high
voltage/frequency transformer that is located in the
negative welding output leg of the machine
and are amplified to about 10KV.
This high frequency/voltage pulse is transferred to the
TIG torch via the high frequency transformer.
This allows the remote starting of the TIG arc without
the need for the tungsten electrode to touch the work.
This high frequency pulse is switched off when the
welding arc is established.
The HF command signals are received from the
microprocessor on the Control Board and stays
on, if the welding arc is not established for about 3
seconds maximum. The HF Board is supplied
from the input power board with 24Vdc and 15Vdc.
HF is disable in Stick and Lift TIG modes.