Miller Electric SYNCROWAVE 250 Technical Manual page 25

26
25
Hall Device
HD1
Stabilizer
Z1
27
Line
Filter
FL1
Current Feedback
Voltage Feedback
Voltage Feedback
AC Or DC Control
1 Power
Weld Current Circuit
External Circuits
Optional
Syncrowave 250
28
11
Voltmeter
Output
V1
Selector
Switch
S4
21
29 22
Integrated
Rectifier
SR2
21
20
18
19
Preflow
Timer
TD3
19
18
Preflow Time
Control
R12
Switch
S9
19
30
Work Weld
Output
Terminal
30
Electrode
Weld Output
Terminal
High
Frequency
Coupling
Coil T3
High
Frequency
Intensity
Control R13
Spark Gaps G
Capacitor
C4
High
Frequency
Transformer
T2
115 VAC
Spot
Timer
TD2
Spot Time
Control
R10
Spot Time
Switch
S8
15 115 Volts AC Duplex Recep-
tacle RC2
Provides connection point for auxil-
iary equipment.
16 Postflow Timer TD1
Controls shielding gas and coolant
postflow time.
17 Gas Valve GS1
Provides shielding gas during the
weld cycle.
18 Preflow Timer TD3, Control
R12, And Switch S9
R12 selects time shielding gas
flows before arc starts. S9 is an in-
tegral part of R12 so that when R12
is turned past zero (0), TD3 is off.
19 Spot Timer TD2, Switch S8,
And Control R10
R10 selects time output is available
when spot welding. S8 selects Off
or spot welding with remote contac-
tor control.
20 High Frequency Transformer
T2
Steps up input voltage and charges
capacitor C4.
21 Spark Gaps G And High Fre-
quency Coupling Coil T3
G provides path for C4 to discharge
into T3. T3 supplies high-frequency
to welding circuit.
22 High Frequency Intensity
Control R13
Changes amount of HF energy
used to start and maintain the arc.
23 Main Rectifier SR1
Changes the ac output from T1 to
full-wave rectified dc.
24 Background Power Source
Provides reduced weld output rip-
ple at low weld output levels.
25 Stabilizer Z1
Smooths dc welding current.
26 Hall Device HD1
Provides current feedback signal to
PC1 through line filter FL1.
27 Line Filter FL1
Filters current feedback signal.
28 Output Selector Switch S4
Provides either AC or DC and out-
put polarity.
29 Integrated Rectifier SR2
Provides dc voltage feedback to
PC1.
30 Electrode And Work Weld
Output Terminals
Provide weld output.
TM-353 Page 21