
Return to Master TOC
Return to Master TOC
| TABLE OF CONTENTS | |||
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Theory of Operation |
| Section E | ||
| General Description | .................................................................................................................... | ||
| Input Power Circuit |
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| Output Rectification, Control Board and Feedback | |||
| High Voltage/High Frequency Circuit | |||
| DC Welding Output |
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| AC Welding Output |
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| SCR Operation |
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| Protective Circuits |
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| Fan As Needed (F.A.N.) | |||
| Thermal Protection | |||
| Overload Protection | |||
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| FIGURE E.1 – PRECISION TIG 275 BLOCK LOGIC DIAGRAM |
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FROM
CONTROL
BOARD
OPTIONAL POWER
CORRECTIONFACTOR
CAPACITORS
POWER
BACKGROUND
CIRCUIT
63.5 VAC
REAR GANG | WORK |
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POLARITY
SWITCH
BYPASS BOARD
FRONT ELECTRODE
HIGH FREQUENCY
to Master TOC
SWITCH
PANEL
RECONNECT
X1
VAC78 X2
AC | DC | CHOKE |
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| SCR |
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BRIDGE |
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AC | DC | SHUNT |
TRANSFORMER
HIGH VOLTAGE TRANSFORMER
REAR ELECTRODE
Return
115 VAC |
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| GAS | VAC | ||
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| THERMOSTAT | GATELEADS FEEDBACK | SOLENOID | 115 | |||||
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| 115 VAC |
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Master TOC
20 VAC
20 VAC
MINIMUM
OUTPUT
CONTROL
MAXIMUM
OUTPUT
CONTROL
CONTROL BOARD
ADVANCED CONTROL
PANEL RECEPTACLE
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| PROTECTION |
| METER |
| STICK |
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| BOARD |
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| TIG |
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| BALANCE | POST | LOCAL/REMOTE | |||||||
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| CONTROL | FLOW |
| SWITCH |
REMOTE
RECEPTACLE
THERMOSTAT
LED's
Return to
PRECISION TIG 275