5 - theory of operation – Miller Electric Legend AEAD-200-LE User Manual
Page 16
TM-428 Page 12
Miller Legend
1
Engine
Supplies force to turn revolving
fields.
2
Revolving Fields (Rotor)
Turn at 1860 rpm maximum for pow-
er/idle and 3000 rpm maximum for
weld. The speed and excitation cur-
rent of the field coils determine volt-
ages in stator windings.
3
Stator Windings
Supply power to exciter, auxiliary
power, and weld circuits.
4
Fuse F1
Protects exciter excitation winding
from overload.
5
Integrated Rectifier SR2
Changes ac output of stator wind-
ings to dc to supply excitation current
to the exciter revolving field.
6
Control Relay CR5
Energizes when voltage is present in
exciter stator to disconnect field
flashing circuit.
7
Idle Module PC1 And Idle Lock
Switch S1
PC1 and S1 control engine speed.
Without a signal from CT1, PC1 low-
ers engine speed to power/idle rpm.
8
Throttle Solenoid TS1
Increases engine speed to weld rpm
when energized.
9
Current Transformer CT1
Senses output from either weld or
100 Hz auxiliary power windings,
and signals PC1 to increase to or
maintain weld rpm.
10 Control Relays CR2, CR3, CR4
CR2 energizes at weld rpm to supply
power to throttle solenoid TS1.
CR3 energizes at power/idle rpm to
bypass fine amperage control R1.
CR4 energizes at power/idle rpm to
provide 50/60 Hz auxiliary power
output.
11 Voltage Regulator Board PC2
And Transformer T1
PC2 monitors 50/60 Hz auxiliary
power voltage through T1, and main-
tains proper output by adjusting field
current.
12 Capacitor Board PC5, Remote
14 Receptacle RC1, Remote
Control Board PC3
PC5 protects unit from high frequen-
cy. RC1 connects remote amperage
and contactor control to unit through
control board PC3.
SECTION 5 – THEORY OF OPERATION
Voltage
Regulator
Board PC2
Current
Transformer
CT1
Circuit
Breaker
CB3
100 Hz
Auxiliary Power
Receptacle RC4
Fuse
F1
Integrated
Rectifier SR2
Revolving
Fields (Rotor)
Fine
Amperage
Control R1
Remote Control
Switch S4
Remote 14
Panel
Remote
Control Board
PC3
Capacitor Board
PC5 And Remote 14
Receptacle RC1
Engine
Idle Module
Control Relays
CR2, CR3, CR4
Idle Lock
Switch S1
12
1
7
10
5
7
16
17
♦
13
♦
12
♦
4
11
9
18
2
PC1
CR3
Throttle
8
Solenoid
TS1
Control
Relay
6
CR5
♦
Voltage
Regulator
60 Hz Auxiliary
Power
Exciter
Stator Windings
3
Weld
100 Hz
Auxiliary
Power