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DESCRIPTION OF OPERATION
0740 800 186
- 30 -
© ESAB AB 2016
The pulse frequency is 65 kHz +/- 1kHz, with a maximum pulse width of 43 - 44 % of the
cycle width. See chapter "Service Instrucions" for screen traces of waveforms and
measurement instructions.
Transistor Q5 controls the primary winding of the pulse transformer on circuit board 15AP1.
20AP1:5 Temperature monitoring
The thermal overload switches, 15ST1 and 15ST2, are normally closed. Terminal T2 of the
circuit board is at 0 V.
15ST2, which is fitted on the heat sink, opens at 75 °C. 15ST1, which is fitted in the winding
of the main transformer, 15TM1, opens at 130 °C.
If either of the switches operates, the power source is stopped, fault code E06 is displayed.
The power source cannot be restarted until it has cooled sufficiently for the switch(es) to
reclose.
20AP1:6 Shunt and current control amplifier
The shunt produces 60 mV at a welding current of 100 A. The shunt response is linear to the
welding current.
If the shunt is not connected to the circuit board, resistor R2 supplies about 1.4 to 1.9 V to
the shunt input. This blocks the current control amplifier, i.e. the power source does not
deliver any welding current.
Summary of Contents for Caddy Tig 1500i TA34
Page 10: ...WIRING DIAGRAM 0740 800 186 10 ESAB AB 2016 Tig 1500i with control panel TA34 ...
Page 11: ...WIRING DIAGRAM 0740 800 186 11 ESAB AB 2016 ...
Page 12: ...WIRING DIAGRAM 0740 800 186 12 ESAB AB 2016 Tig 2200i with control panels TA33 and TA34 ...
Page 13: ...WIRING DIAGRAM 0740 800 186 13 ESAB AB 2016 ...
Page 20: ...DESCRIPTION OF OPERATION 0740 800 186 20 ESAB AB 2016 ...