Red-D-Arc D502K 5+4, Technical Manual

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TM-4412 Page 32
D502K 5+4
SECTION 9 – EXPLANATION OF ELECTRICAL PARTS
elect_parts 1/01
9-1. Safety Precautions – Read Before Using This Guide
Y
WARNING: ELECTRIC SHOCK can kill.
D
Disconnect input power or stop engine before servicing.
D
Do not touch live electrical parts.
D
Do not operate machines with covers removed.
D
Have only qualified persons install, use, or service equipment.
9-2. Explanation Of Electrical Parts
PART NAME FUNCTION PICTURE CIRCUIT SYMBOL
CAPACITOR A device that stores electrical energy. Large
capacitors or a “bank” of capacitors can be
used to “smooth out” the DC welding arc in a
MIG welding power source. Smaller “disk”
capacitors can be used for HF protection.
C1 C1
POLARIZED NON-POL.
CIRCUIT BREAKER A protection device that breaks a circuit when
current levels exceed its rating. Unlike a fuse
that needs to be replaced when blown, a
circuit breaker can be reset.
CB1
DIODE A device that allows current to flow in one
direction only. Most common use is to
change AC to DC.
D1
FUSE A protection device, usually an enclosed
piece of wire that melts and breaks the circuit
when the current exceeds the fuse rating.
F1
HALL DEVICE Produces a small DC voltage proportional to
the current it is sensing (usually welding
current). This feedback signal can be used to
regulate the welding output (line voltage
compensation). It may even be used to drive
an ammeter.
HD1
RESISTOR A device which resists the flow of electric
current. Uses include limiting the current for a
motor brake circuit in a wire feeder and for
discharging a capacitor.
FIXED
FIXED TAPPED
R1
R1
POTENTIOMETER
OR
RHEOSTAT Both devices have a moveable brush that
makes contact along a resistor, allowing you
to easily change the resistance measured at
the brush (sometimes referred to as a wiper).
Their primary purpose is to give the operator
a way to adjust welding parameters such as
wire speed, preflow time, voltage,
inductance, etc.
VARIABLE
R1