YATO YT-81352 User manual

SUMMARY
Inverter DC MMA Arc Welding Machine
IMPORTANT: Read this Owner’s Manual Completely before attempting to use this
equipment. Save this manual and keep it handy for quick reference. Pay particular
attention to the safety instructions we have provided for your protection. Contact your
distributor if you do not fully understand this manual.
YT-81352
YT-81353
I

SUMMARY
CONTENT
§1 SAFETY............................................................................................................................................. 1
§1.1 Signal Explanation ....................................................................................................................... 1
§1.2 Arc Welding Damage ................................................................................................................... 1
§1.3 The knowledge of Electric and Magnetic Fields.......................................................................... 4
§2 Summary............................................................................................................................................ 5
§2.1 Brief Introduction ........................................................................................................................ 5
§2.2 Working Principle ........................................................................................................................ 5
§2.3 Volt-Ampere Characteristic.......................................................................................................... 6
§3 Installation & Adjustment ................................................................................................................ 7
§3.1 Parameters.................................................................................................................................... 7
§3.2 Duty cycle & Over heat ............................................................................................................... 7
§3.3 Welding polarity connection way................................................................................................. 8
§3.3.1 MMA (take YT-81352 for an example) ................................................................................ 8
§4 Operation control and connectors ................................................................................................... 9
§4.1 Layout for front & rear panel (example for YT-81352)............................................................... 9
§4.2 parameters adjustment ............................................................................................................... 10
§4. 3 Welding operation..................................................................................................................... 10
§4.3.1 Striking arc way.................................................................................................................. 10
§4.4.2 Manipulation of electrode....................................................................................................11
§4.4 Welding parameters.....................................................................................................................11
§4.4.1 Joint form in MMA..............................................................................................................11
§4.4.2 Electrode selection...............................................................................................................11
§4.5 Arc Welding Defect and Prevent Method .................................................................................. 12
§4.6 Operation Environment.............................................................................................................. 13
§4.7 Operation Notices ...................................................................................................................... 14
§5 Maintenance & Troubleshooting ................................................................................................... 15
§5.1 Maintenance............................................................................................................................... 15
§5.2 Troubleshooting ......................................................................................................................... 16
§5.3 Electrical principle drawing ....................................................................................................... 19
II

SUMMARY
§1SAFETY
§1.1 Signal Explanation
yThe above signals mean warning! Notice! Running parts and getting an electric shock or
thermal parts will take damage for your body or others. The corresponding notices are as follows.
It is quite a safe operation after taking several necessary protection measures.
§1.2 Arc Welding Damage
yThe following signals and word explanations are to some damages for your body or others
happening on the welding operation. While seeing these, please remind of yourself or others to
be dangerous.
yOnly ones who are trained professionally can install, debug, operate, maintain and repair the
equipment.
yDuring the operation, non-concerned people should be lift, especially for children.
yAfter shut off the machine power, please maintain and examine the equipment according to §5
because of the DC voltage existing in the electrolytic capacitors.
ELECTRIC SHOCK CAN KILL.
yNever touch electrical parts.
yWear dry, hole-free gloves and clothes to insulate yourself.
yInsulate yourself from work and ground using dry insulation.Make certain the insulation is
large enough to cover your full area of physical contact with work and ground.
yTake carefully when using the equipment in small place, falling-off and wet circumstance.
yNever close the machine power before installation and adjustment.
yEnsure to install the equipment correctly and ground the work or metal to be welded to a good
electrical (earth) ground according to the operation manual.
yThe electrode and work (or ground) circuits are electrically “hot” when the welder is on. Do not
touch these “hot” parts with your bare skin or wet clothing. Wear dry, hole-free gloves to insulate
hands.
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SUMMARY
yIn semiautomatic or automatic wire welding, the electrode, electrode reel, welding head,
nozzle or semiautomatic welding gun are also electrically “hot”.
yAlways be sure the work cable makes a good electrical connection with the metal being welded
The connection should be as close as possible to the area being welded.
yMaintain the electrode holder, work clamp, welding cable and welding machine in good, safe
operating condition. Replace damaged insulation.
yNever dip the electrode in water for cooling.
yNever simultaneously touch electrically “hot” parts of electrode holders connected to two
welders because voltage between the two can be the total of the open circuit voltage of both
welders.
yWhen working above floor level, use a safety belt to protect yourself from a fall should you get
a shock.
FUMES AND GASES CAN BE DANGEROUS.
yWelding may produce fumes and gases hazardous to health. Avoid breathing these fumes and
gases. When welding, keep your head out of the fume. Use enough ventilation and/or exhaust at
the arc to keep fumes and gases away from the breathing zone. When welding with electrodes
which require special ventilation such as stainless or hard facing or on lead or cadmium plated
steel and other metals or coatings which produce highly toxic fumes, keep exposure as low as
possible and below Threshold Limit Values using local exhaust or mechanical ventilation. In
confined spaces or in some circumstances, outdoors, a respirator may be required. Additional
precautions are also required when welding on galvanized steel.
yDo not weld in locations near chlorinated hydrocarbon vapors coming from degreasing,
cleaning or spraying operations. The heat and rays of the arc can react with solvent vapors to
form phosgene, a highly toxic gas, and other irritating products.
yShielding gases used for arc welding can displace air and cause injury or death. Always use
enough ventilation, especially in confined areas, to insure breathing air is safe.
yRead and understand the manufacturer’s instructions for this equipment and the consumables
to be used, including the material safety data sheet and follow your employer’s safety practices.
ARC RAYS CAN BURN.
yUse a shield with the proper filter and cover plates to protect your eyes from sparks and the
rays of the arc when welding or observing open arc welding.
yUse suitable clothing made from durable flame-resistant material to protect your skin and that
2

SUMMARY
of your helpers from the arc rays.
yProtect other nearby personnel with suitable, non-flammable screening and /or warn them not
to watch the arc nor expose themselves to the arc rays or to hot spatter or metal.
SELF-PROTECTION
yKeep all equipment safety guards, covers and devices in position and in good repair. Keep
hands, hair, clothing and tools away from V-belts, gears, fans and all other moving parts when
starting, operating or repairing equipment.
yDo not put your hands near the engine fan. Do not attempt to override the governor or idler by
pushing on the throttle control rods while the engine is running.
DO NOT adds the fuel near an open flame welding arc or when the engine
is running. Stop the engine and allow it to cool before refueling to prevent spilled fuel from
vaporizing on contact with hot engine parts and igniting. Do not spill fuel when filling tank. If
fuel is spilled, wipe it up and do not start engine until fumes have been eliminated.
WELDING SPARKS can cause fire or explosion.
yRemove fire hazards from the welding area. If this is not possible, cover them to prevent the
welding sparks from starting a fire. Remember that welding sparks and hot materials from
welding can easily go through small cracks and openings to adjacent areas. Avoid welding near
hydraulic lines. Have a fire extinguisher readily available.
yWhere compressed gases are to be used at the job site, special precautions should be used to
prevent hazardous situation.
yWhen not welding, make certain no part of the electrode circuit is touching the work or ground.
Accidental contact can cause overheating and create a fire hazard.
yDo not heat, cut or weld tanks, drums or containers until the proper steps have been taken to
insure that such procedures will not cause flammable or toxic vapors from substances inside.
They can cause an explosion even though they have been “cleaned”.
yVent hollow castings or containers before heating, cutting or welding. They may explode.
ySparks and spatter are thrown from the welding arc. Wear oil free protective garments such as
leather gloves, heavy shirt, cuff less trousers, high shoes and a cap over your hair. Wear ear plugs
when welding out of position or in confined places. Always wear safety glasses with side shields
when in a welding area.
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SUMMARY
yConnect the work cable to the work as close to the welding area as practical. Work cables
connected to the building framework or other locations away from the welding area increase the
possibility of the welding current passing through lifting chains, crane cables or other alternate
circuits. This can create fire hazards or overheat lifting chains or cables until they fail.
Rotating parts may be dangerous.
yUse only compressed gas cylinders containing the correct shielding gas for the process used
and properly operating regulators designed for the gas and pressure used. All hoses, fittings, etc.
should be suitable for the application and maintained in good condition.
yAlways keep cylinders in an upright position securely chained to an undercarriage or fixed
support.
yCylinders should be located:
-Away from areas where they may be struck or subjected to physical damage.
-A safe distance from arc welding or cutting operations and any other source of heat, sparks,
or flame.
yNever allow the electrode, electrode holder or any other electrically “hot” parts to touch a
cylinder.
yKeep your head and face away from the cylinder valve outlet when opening the cylinder valve.
yValve protection caps should always be in place and hand tight except when the cylinder is in
use or connected for use.
§1.3 The knowledge of Electric and Magnetic Fields
Electric current flowing through any conductor causes localized Electric and Magnetic
Fields (EMF). The discussion on the effect of EMF is ongoing all the world. Up to now, no
material evidences show that EMF may have effects on health. However, the research on damage
of EMF is still ongoing. Before any conclusion, we should minimize exposure to EMF as few as
possible.
In order to minimize EMF, we should use the following procedures:
yRoute the electrode and work cables together – Secure them with tape when possible.
yAll cables should be put away and far from the operator.
yNever coil the power cable around your body.
yMake sure welding machine and power cable to be far away from the operator as far as
possible according to the actual circumstance.
yConnect the work cable to the workpiece as close as possible to the area being welded.
yThe people with heart-pacemaker should be away from the welding arc.
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SUMMARY
§2 Summary
This operation manual is suitable for the model of YT-81352, YT-81353.
§2.1 Brief Introduction
YT-series welders are general MMA arc welder which adopts the latest pulse
width modulation (PWM) technology and the insulated gate bipolar transistor (IGBT)
power module. It uses digital control system. It can change work frequency to
medium frequency so as to replace the traditional hulking work frequency transformer
with the cabinet medium frequency transformer. Thus, it is characterized with
portable, small size, low consumption and etc.
YT-series have excellent performances:real time display and current preset makes
it convenient to use; fan demand makes the machine save the energy; constant current
output makes welding arc more stable; fast dynamic response speed reduces the
impact from the arc length fluctuation to the current; accurate stepless current
adjustment and pre-setting function. There are also some automatic protection
functions for under voltage, over heat, etc. inside the welders,when the problems
listed before occurred, the alarm on the front panel is light and at the same time the
output current will be cut off. It can self-protect and prolong the using life and greatly
improved the reliability and practicability of the welders.
MMA——Manual Metal Arc welding;
PWM——Pulse-Width Modulation;
IGBT——Insulation Gate Bipolar Transistor;
§2.2 Working Principle
The working principle of YT-series welder is shown as the following figure.
Single phase 220V-240V±10% work frequency (50/60 Hz) AC is rectified into DC
(about 300V), then is converted to medium frequency AC (about 20KHz) by inverter
device (IGBT module), after reducing voltage by medium transformer (the main
transformer) and rectified by medium frequency rectifier (fast recovery diodes), and is
outputted by inductance filtering. The circuit adopts current feedback control
5

SUMMARY
technology to insure current output stably. Meanwhile, the welding current parameter
can be adjusted continuously and steplessly to meet with the requirements of welding
craft.
Rectify Inverter
Medium
frequency
transformer
Medium
frequency
rectify
Hall device
Current positive-
feedback control
Single phase,AC DC AC DC
220/230V50/60Hz
AC DC
§2.3Volt-Ampere Characteristic
YT-series welders have excellent volt-ampere characteristic, seeing the following
graph. In MMA welding, the relation between the rated loading voltage U2and
welding current I2 is as follows:
When I2İ600AˈU2˙20ˇ0.04 I2˄V˅˗ When I2˚600AˈU2˙44˄V˅.
64
44
20
0 600 I
2
˄A˅
U
2
˄V˅
Working
point
Volt-ampere characteristic
The relation of the rated loading
voltage&welding current
6

INSTALLATION AND ADJUSTMENT
§3 Installation & Adjustment
§3.1 Parameters
Models
Parameters
YT-81352 YT-81353
Input power Single phaseˈ
220-240V±10%, 50/60Hz
Single phase
ˈ
220-240V
±
10%,100V~120V
±
10%, 50/60Hz
Rated input current
˄
A
˅
46.4A
43.3A/110V,46.4A/230V
Rated input power
˄
KW
˅
8.5
3.8/ 1 1 0 V, 8.5/230V
Power factor
0.8
Welding current range
˄
A
˅
20

210A
20A

130A/110V,20A~210A/230V
Max no-load voltage(V)
67
57V/110V,67V/230V
Efficiency
ı
80
ˁ
Duty cycle˄40ćˈ10 minutesˈrefer to§3.2
˅
210A/30%
130A/30%,210A/30%
115A/100%
71A/100%,115A/100%
Protection class
IP21s
Insulation class
F
Dimensions of Machine
˄
L
×
W
×
H
˅˄
mm
˅320*145*275 320*145*275
Note:
1. The above parameters are subject to change with the improvement of machines.
§3.2 Duty cycle & Over heat
The letter “X” stands for duty cycle, which is defined as the proportion of the time
that a machine can work continuously within a
certain time (10 minutes). The rated duty cycle
means the proportion of the time that a machine can
work continuously within 10 minutes when it
outputs the rated welding current.
The relation between the duty cycle “X” and the
output welding current “I” is shown as the right
figure.
If the welder is over-heat, the IGBT over-heat
protection unit inside it will output an instruction to cut output welding current, and
brighten the over-heat pilot lamp on the front panel. At this time, the machine should
be relaxed to cool the fan. When operating the machine again, the welding output
current or the duty cycle should be reduced.
I˄A˅
0
100ˁ
115 210
X
30%
The relation between duty cycle and
welding current for YT-81352,YT-81353
supplied by 230V/50Hz
7

INSTALLATION AND ADJUSTMENT
§3.3 Welding polarity connection way
§3.3.1 MMA
Connection DCEP is only supported.
YT-81352
YT-81353
workpiece
electrode
DCEP
Welding holder
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OPERATION CONTROL AND CONNECTORS
§4Operation control and connectors
§4.1 Layout for front & rear panel (example for YT-81352)
YT-81352 and YT-81353 have the same penal;
1) Alarm lamp Over-heat or over-current.
2) MMA lamp
3) LIFT TIG lamp
4) Welding mode key
5) Earth connection Negative polarity output
6) Welding connection Positive polarity output
7) Value display Display the pre-setting and realtime parameter value.
8) VRD lamp VRD parameter indicator lamp.
9) HS lamp Hot start parameter indicator lamp.
10) AF lamp Arc force parameter indicator lamp.
11) Encoder knob Set welding parameter values.
12) Parameters option key
13) Cable clamp Fastened the mains cable
14) Mains switch.
9

OPERATION CONTROL AND CONNECTORS
§4.2 parameters adjustment
Take example for YT-81352. Welding current range is 20A
210A at 220-240V, 20A~130A at 100V~120V.Hot start current
range is 0%~100%. Arc force value range is 0%~100%.
YT-series welder has the pre-setting function of welding
current,hot start current, arc force value. Before welding,
pitching the parameter options by pressing Parameters
option key and adjusting parameter values by turn the knob, the parameter values
will be show on the display.It is convenient to set parameters and adjust
accurately. Change the welding mode by pressing the welding mode key. Switch
on or off the VRD function by pressing the knob for 3 seconds.
§4. 3 Welding operation
§4.3.1 Striking arc way
zKnocking arc: take the electrode upright to touch the workpiece, after forming
short circuit, quickly lift up about 2~4 mm, and arc will be ignited. This method
is difficult to master. But in the welding for the brittle or hard steel, it is better to
use knocking way.
electrode
workpiece
electrode electrode
workpiece workpiece
Take the electrode upright The Electrode touch the workpiece Lift up for about 2-4mm
upright
up
touch
24mm
electrode
workpiece
weld
1
2
3
2
1-electrode moving; 2-the electrode swing right &left; 3-the electrode move along weld
A
10

OPERATION CONTROL AND CONNECTORS
zLifting arc: take the electrode to scrape the workpiece for striking arc. But it may
cause the arc scratch, so must to lift arc in the groove.
§4.4.2 Manipulation of electrode
In MMA welding, there are three motions to being matched in the end of
electrode: the electrode moving to the molten pool along axes; the electrode swing
right and left; the electrode moving along welding way.
The operator can choose the manipulation of electrode based on welding joint
sharp, welding position, electrode spec, welding current and operation skill, etc.
The details please refer toljWelding DictionaryNJP69, Volume 1 of Edition 2.
§4.4 Welding parameters
§4.4.1 Joint form in MMA
In MMA welding, the common basic joint form: butt joint, lap joint, corner joint
& T joint.
§4.4.2 Electrode selection
The electrode diameter selection is based on the workpiece thickness, welding
position, joint form, welding layer, etc. Please refer to the following table.
The welding current reference for different electrode diameter
Electrode
diameter/mm 1.6 2.0 2.5 3.2
Welding current/A 2540 4060 5080 100130
The relation between the welding current(I)’factor(K) & electrode diameter(d) (I˙K×d: Carbon electrode)
Electrode
diameter/mm
1.6 22.5 3.2
Factor/K 2025 2530 3040
Notice: the above parameters originate fromljWelding DictionaryNJP66P67, Volume
butt joint lap joint corner joint T joint
11

OPERATION CONTROL AND CONNECTORS
1 of Edition 2.
zElectrode should be drying according to user manual before using. For reducing
the hydrogen of the molten pool and welding seam, and avoiding the blowhole
and cold crack.
zIn the welding process, the arc must not be too long; otherwise, it will cause
unstable arc burning, large spatter, light penetration, undercut, blowhole, etc. If
the arc is too short, it will cause electrode stick.
zIn MMA welding the arc length is usually equal to 0.5~1.0 time of the electrode
diameter. The basic electrode’s arc length is not beyond the electrode diameter,
it’s better to choose the short arc welding; the acid electrode’s arc length is equal
to the electrode diameter.
§4.5 Arc Welding Defect and Prevent Method
Defect name
Caused reasons
Prevent methods
Welding
seam doesn’t
meet the
requirement
The groove angle is not proper
The root face and assembly gap is not equal
Welding technics parameters are unreasonable
The welder’s operation skill is lower
Choosing the proper groove angle & assembly
gap, improve the assembly quality
Choosing the proper welding parameters
Improve the operation skill of welders
Undercut
Over current
Arc length is too long
The electrode angle is wrong
Manipulation of electrode is not proper
Choosing the proper welding current & speed
The arc can’t be drawn too long
The electrode angle should be proper
Manipulation of electrode should be correct
Incomplete
penetration
The groove angle or gap is too small, the root
face is too big
Welding parameters are not su
itable, or the
assembly is not good
The welder’s operation skill is lower
Correctly to choose and process the groove size
Correctly to assemble and ensure clearance
Choosing the suitable welding current & speed
Improve the operation skill of welders
Incomplete
fusion
The welding thermal input is too low
The arc direction is lean
There are rust & dust on the side of groove
The slag between the layers is not cleared well
Correctly to choose the welding parameters
Operation seriously
Enhance the clearness of layers
Overlap The temperature of molten pool is too high
The liquid metal concretes slowly
Choosing parameters based on the welding
different position
Strictly to control the molten hole size
Crater The crater time lasts too short
Over current in the welding of thin plate
In the crater, electrode should be stayed for a
short time or round to manipulate electrode
after the molten pool is filled in by metal, take
to the side for crater
12

OPERATION CONTROL AND CONNECTORS
Defect name
Caused reasons
Prevent methods
Welding
seam doesn’t
meet the
requirement
The groove angle is not proper
The root face and assembly gap is not equal
Welding technics parameters are unreasonable
The welder’s operation skill is lower
Choosing the proper groove angle & assembly
gap, improve the assembly quality
Choosing the proper welding parameters
Improve the operation skill of welders
Undercut
Over current
Arc length is too long
The electrode angle is wrong
Manipulation of electrode is not proper
Choosing the proper welding current & speed
The arc can’t be drawn too long
The electrode angle should be proper
Manipulation of electrode should be correct
Incomplete
penetration
The groove angle or gap is too small, the root
face is too big
Welding parameters are not su
itable, or the
assembly is not good
The welder’s operation skill is lower
Correctly to choose and process the groove size
Correctly to assemble and ensure clearance
Choosing the suitable welding current & speed
Improve the operation skill of welders
Incomplete
fusion
The welding thermal input is too low
The arc direction is lean
There are rust & dust on the side of groove
The slag between the layers is not cleared well
Correctly to choose the welding parameters
Operation seriously
Enhance the clearness of layers
Blowhole
There are some dust like oil, rust or water on
the work piece surface and groove
The coating of electrode is damped& is not
drying
Under current or over speed in the welding
The arc is too long or lean burning, the molten
pool protection is not good
Over current, the coating of electrode falls off
and lose protection
Manipulation of electrode is not proper
Clear out the dust around groove for about 20
30mm
Strictly to dry the electrode according to manual
Correctly to choose parameters and to operate
Using the short arc operation
Welding operation in the field sho
uld have
anti-wind protection
Don’t use the invalid electrode
Inclusion &
slag
inclusion
The slag clears bad in the middle layer in the
welding process
Under current or over speed in the welding
Welding operation is not proper
The welding material can not match the work
piece
The groove design & processing are not
proper
Choosing the electrode of good slag
detachability
Strictly to clear the slag in the layers
Correctly to choose the welding parameters
Adjusting the electrode angle and manipulation
way
Defect name
Caused reasons
Prevent methods
Hot crack
In the process of solidification, the inter
crystal segregation is seriously caused. At the
same time, with the effect of welding stress,
the hot crack is formed.
Adjust the structure of welding material.
Adopt the basic electrode.
Cold crack
Three reasons will cause cold crack:
The structure turned from the marten site
T
he residual stress caused by big restraint
intensity
The residual hydrogen in welding gap.
Adopt low hydrogen type basic electrode.
Bake under the instruction before use.
Remove the feculence
before use, reduce the
percentage of hydrogen
Adopt appropriate parameters and heat input
After welding, do dehydrogenation at once.
§4.6Operation Environment
·Height above sea level is below 1000m.
·Operation temperature range:-100C+400C.
·Relative humidity is below 90 %( +200C).
·Preferably site the machine some angles above the floor level, the maximum angle
does not exceed 150.
·Protect the machine against heavy rain or in hot circumstance against direct sunshine.
13

OPERATION CONTROL AND CONNECTORS
·The content of dust, acid, corrosive gas in the surrounding air or substance can not
exceed normal standard.
·Take care that there is sufficient ventilation during welding. There is at least 30cm
free distance between the machine and wall.
§4.7Operation Notices
·Read §1 §4.2 carefully before attempting to use this equipment.
·Connect the ground wire with the machine directly.
·Input power must be AC as one phase, 50Hz, 220/240V. Forbid working in lacking
any phaseDŽ
·In case closing the power switch, no-load voltage may be exported. Do not touch the
output electrode with any part of your body.
·Before operation, no concerned people should be left. Do not watch the arc in
unprotected eyes.
·Ensure good ventilation of the machine to improve duty ratio.
·Turn off the engine when the operation finished to economize energy sources.
·When power switch shuts off protectively because of failure. Don’t restart it until
problem is resolved. Otherwise, the range of problem will be extended.
14

MAINTENANCE AND TROUBLESHOOTING
§5 Maintenance & Troubleshooting
§5.1 Maintenance
In order to guarantee that arc welding machine works high-efficiently and in
safety, it must be maintained regularly. Let customers understand the maintenance
methods and means of arc welding machine more , enable customers to carry on
simple examination and safeguarding by oneself, try one's best to reduce the fault rate
and repair times of arc welding machine, so as to lengthen service life of arc welding
machine .Maintenance items in detail are in the following table.
Ɣ:DUQLQJ)or safety while maintaining the machine, please shut off the supply
power and wait for 5 minutes, until capacity voltage already dropsto safe voltage
36V.
Date
Maintenance items
Daily
examination
Observe that whether panel knob and switch in the front and at the back of
arc welding machine are flexible and put correctly in place. If the knob has not
been put correctly in place, please correct; If you can't correct or fix the knob ,
please replace immediately;
If the switch is not flexible or it can't be put correctly in place, please replace
immediately; Please get in touch with our company maintenance service
department if there are no accessories.
After turn-on power, watch/listen to that whether the arc welding machine
has shaking, whistle calling or peculiar smell. If there is one of the above
problems, find out the reason to get rid of; if you can't find out the reason,
Please contact local this area our company agent or the branch company.
Observe that whether the display value of LED is intact. If the display
number is not intact, please replace the damaged LED. If it still doesn’t work,
please maintain or replace the display PCB.
Observe that whether the min/max value on LED accords with the set value.
If there is any difference and it has affected the normal welding craft, please
adjust it.
Check up that Whether fan is damaged and is normal to rotate or control. If
the fan is damaged, please change immediately. If the fan does not rotate after
the arc welding machine is overheated , observe that whether there is something
blocked in the blade, if it is blocked, please get rid of ; If the fan does not rotate
after getting rid of the above problems, you can poke the blade by the rotation
direction of fan. If the fan rotates normally, the start capacity should be
replaced; If not, change the fan.
Observe that whether the fast connector is loose or overheated. if the arc
welding machine has the above problems, it should be fastened or changed.
Observe that Whether the current output cable is damaged. Ifit is damaged, it
should be wrapped up, insulated or changed.
Monthly
examination
Using the dry compressed air to clear the inside of arc welding machine.
Especially for clearing up the dusts on radiator, main voltage transformer,
inductance, IGBT module, the fast recover diode and PCB,etc.
15

MAINTENANCE AND TROUBLESHOOTING
Check up the bolt in arc welding machine, if it is loose, please screw down it.
If it is skid, please replace. If it is rusty, please erase rust on bolt to ensure it
works well.
Quarter-
yearly
examination
Whether the actual current accords with the displaying value. If they do not
accord, they should be regulated. The actual current value can be measured by
the adjusted plier-type ampere meter.
Yearly
examination
Measure the insulating impedance among the main circuit, PCB and case, if it
below 1M¡, insulation is thought to be damaged and need to change , and need
to change or strengthen insulation.
§5.2 Troubleshooting
zBefore arc welding machines are dispatched from the factory, they have already
been debugged accurately. So forbid anyone who is not authorized by our
company to do any change to the equipment!
zMaintenance course must be operated carefully. If any wire becomes flexible or is
misplaced, it maybe potential danger to user!
zOnly professional maintenance personal who is authorized by our company could
overhaul the machine!
zGuarantee to shut off the arc welding machine’s power before turn on the outline
of the equipment!
zIf there is any problem and has no the authorized professional maintenance
personal of our company, please contact local our company agent or the branch
company!
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If there are some simple troubles of YT-series welding machines, you can consult the following
overhauling chart:
S/N
Troubles
Reasons
Solutions
1Turn on the power source, and fan works,
but the power light is not on.
The power light damaged or
connection is not good
Test and repair the inside
circuit of power light Pr3
Power PCB failures
Repair or change power PCB
Pr2
2
Turn on the power source, and the power
light is on, but fan doesn’t work
There is something in the fan
Clear out
The fan motor damaged
Change fan motor
3Turn on the power source, and the power
light is not on, and fan doesn’t work
No input voltage
Check whether there is input
voltage
Overvoltage (Input voltage is
too much or not)
Check input voltage
4 No no-load voltage output
There is trouble inside the
machine
Check the main circuit, Pr1
and Pr2
5No current output in the welding
Welding cable is not connected
with the two outpu
t of the
welder.
Connect the welding cable to
the welder’s output
Welding cable is broken
Wrap, repair or change the
welding cable
Earth cable is not connected or
loosen Check the earth clamp
6Not easy to start arc in the welding, or easy
to cause sticking
The plug loosen or connect not
well
Check and tighten the plug
Oil or dust covered the
workpiece Check and clear out
MMA/TIG welding selection
is wrong Selecting the MMA welding
7
The arc is not stable in the welding process
The arc force is too small
Increase the arc force
8 The welding current can not be
adjusted
The welding current
potentiometer in the front
panel connection not so good
or damaged
Repair or change the
potentiometer
9
The penetration of molten pool is not
enough(MMA)
The welding current adjusted
too low
Increase the welding current
The arc force adjusted too
small Increase the arc force
10 Arc blow
Airflow disturbance
Use the shelter from airflow
The electrode eccentricity
Adjust the electrode angle
Change the electrode
Magnetic effect
Incline the electrode to the
opposite way of the magnetic
blow
Change the position of earth
clamp or add earth cable in
the two side of workpiece
Use the short arc operation
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11 The alarm light is on
Over heat
protection
Over welding
current
Induce the welding current
output
Working time
too long
Induce the duty cycle (interval
work)
Ov
er current
protection
Unusual
current in the
main circuit
Test and repair the main circuit
and drive PCB (Pr1)
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