Weiro WP-120A User manual

THANKS FOR PURCASHING OUR PRODUCT
WP –120A
INVERTER PLASMA CUTTING MACHINE
W E I R O
OPERATION MANUAL
(Read the manual carefully before installation, operation and maintenace)
Safety Depends on You
WEIRO are welding and cutting equipment is designed and built with safety
in mind. However, your overall safety can be increased by proper installation...
and thoughtful operation in your part. DO NOT INSTALL, OPERATE OR
REPAIR THIS EQUIPMENT WITHOUT READING THIS MANUAL AND
THE SAFETY PRECAUTIONS CONTAINED THROUGHOUT. And, most
importantly, think before you act and be careful.
C V. A N U G R A H D U TA N I A G A
Jln. Arief Rahman Hakim 51 Komplek Ruko 21 Klampis Blok D-1
Telp. 031 –5990089, 5997259 (Hunting)
Fax. [phone]
Email : [e-mail]

１６
Index
1. Principle &Technical
data…………………………………………………….(1 )
2. Features &
Applications……………………………………………………....(5 )
3. Installation
Guide………………………………………………………….….(6 )
4. Operating
Instruction …………...…………………………………………....(9)
5. Repair &
Maintenance……………………………………………………......(12)

１７
Principle & Technical data
WP 120A Block diagram of principle
3~380V/50Hz
Figure 1: Block diagram of principle
This series of cutting machines applies IGBT Middle Frequency inverter technology. Line
frequency 3-phase input volt are rectified by rectifier, inverted into MF AC by IGBT components,
insulated by MF transformer, rectified and filtered by MF rectifier, then outputs DC power
suitable for cutting. After this process, the cutter’s dynamically responsive speed has been greatly
increased, so the transformer and reactor size and weight are reduced noticeably, thus achieving
energy-saving.
Power sources enjoy sound drooping outer ability and anti-fluctuating ability due to loop control
of reasonable logic circuit design. First, the signals of the set parameters transmit into set circuit
to adjust output current. Secondly, the feedback circuit amplifies output current to get feedback
signal. PWM circuit compares the set signals with feedback signals to determine output pulse
width. Finally, driving circuit will control pulse to amplify power to drive IGBT. Meanwhile,
protection circuit monitor over-current, low-voltage and overheat phenomenon to ensure reliable
cutting. Because of reasonable sequence of logic control, the cutters can perform pre-gas flow,
HF arc start, cutting and post-gas flow convenient for operators.
U0
I2min I2max
Figure 2: Model WP 120AVolt-Ampere curve
Rectifier
MF
Inverter
MF
Transformer
Rectifier &
Filter
Control circuit
High frequency arc start
U（V）
I(A)

１８
1. Main technical parameters
Items Model
WP120A
Input volt (V)
Three phase 380 /
50Hz
Rated input capacity（KVA）
25.7
Rated input current（A）
37
Range of output current（A）
30－120
Open load （V）
345
Rated load volt（V）
128
Rated duty cycle
60%
Air pressure for cutting torch
（MPa）
0.45
Gas flow rate（L/min）
250
Max cutting thickness for carbon
steel（mm）
35
Optimum cutting thickness for
carbonsteel
1-30
Dimension
576×297×557
Weight（Kg）
43.5
Insulated class of main
transformer
H
Insulated class of output
reactor
B
Table 1: Parameter Specification

１９
2. Main circuit diagram
WP120A
Figure 3: Main Circuit Diagram of WP 120A

２０
3.Main components list
WP120A
No
Name
Model
Remark
K1
Circuit breaker
DZ47-63D (40A/3P)
D1
Three-phase rectified module
MDS100A-1200V (big)
R1
Varistor
MYL1 625/5
V1～2
IGBT module
SKM100GB128D
C5
Polypropylene capacitor
MFD-DA01 4uF/500VAC
IGBTZRB
IGBT protection Board
NBC-500Ⅱ.5.1.0
T1
Main transformer
LGK-100.3.1.0
D2
Fast recovery diode module
DWC2F100N060S
D3
Fast recovery diode module
DWC2F100P060S
L2
Current exchange inductor
ZX7-400Ⅲ.5.2.0
T4
Transformer for ZKB/QDB
ATIG-500.3.1-8
F1
Fuse
2A(5×20)
M
Fan
AK2072HB
220V single
phase
SW
Thermal switch
JUC-6F 70℃ (close)
QDB
Drive board
ZX7-400Ⅲ.7.0
ZKB
Main control board
LGK-100.6.0
DF
Electromagnet valve
DF2-5(0.8MPa)
AC36
Switch
KCD4-202
Potentiometer
WH118-2W-4.7KΩ
Adjusting
ampere
Table 2: Main Components List of WP 100A / 120A

２１
Features & Applications
This series inverter air plasma cutting machines, which are new-designed for metal
processing, apply IGBT as well as PWM (Pulse width Modulation) soft switch technology.
This series cutting machines can cut all types of metal materials, especially for high alloy
steel and non-ferrous metals that can not be cut by using flame cutting machine. This series
cutting machines enjoys reasonable static characteristic and sound dynamic characteristic,
can perform HF arc start.
Features and benefits:
HF inverter, small size, light weight.
Soft switch transform, high efficiency.
Delayed post-flow can protect plasma torch effectively.
Outstanding cutting quality with trim and slick edge.
Short-circuit protection inside cutting torch.
HF arc-starting, easy to strike.
Non-source power factor compensation technology, high PF.
2 cycle / 4cycle operating modes provided.
Thermal protection provided.
Applications:
Suitable for cutting mild steel, alloy steel, stainless steel, Copper, Aluminum and other
non-ferrous metals.
This series cutting machines manufacturing strictly comply with National standard
GB15579.1-2004<<”Arc welding equipment” Chapter one: Welding Power Source>>

２２
Installation Guide
1．Pre-installation
1.1 Installation Environment
The WP series is designed for use in adverse environments. Examples of
environments with increased adverse conditions are:
In locations in which freedom of movement is restricted, so that the operator is
forced to perform the work in a cramped (kneeling, sitting or lying) position
with
physical contact with conductive parts;
In locations which are fully or partially limited by conductive elements, and in
which there is a high risk of unavoidable or accidental contact by the operator;
In wet or damp hot locations where humidity or perspiration considerably
reduces
the skin resistance of the human body and the insulation properties of
accessories.
Environments with adverse conditions do not include places where electrically
conductive parts, in the near vicinityof the operator, which can cause increased
hazard, have been insulated.
1.2. Installation Location
Be sure to locate the welder according to the following guidelines:
· In areas, free from moisture and dust.
· Ambient temperature between 0 degrees C to 40 degrees C.
· In areas, free from oil, steam and corrosive gases.
· In areas, not subjected to abnormal vibration or shock.
· In areas, not exposed to direct sunlight or rain.
· Place at a distance of 12" (304.79mm) or more from walls or
similar boundaries that could restrict natural airflow for cooling.

２３
1.3 Power Source Connections
Warning
Thermal Arc advises that this equipment be electrically connected by a
qualified electrician.
ELECTRIC SHOCK can kill; SIGNIFICANT DC VOLTAGE is present after
removal of input power.
DO NOT TOUCH live electrical parts.
SHUT DOWN welding power source, disconnect input power employing
lockout/tagging procedures.
Lockout/tagging procedures consist of padlocking line disconnect switch in
open position.
Removing fuses from fuse box, or shutting off and red-tagging circuit breaker
or other disconnecting device.
1.4. Power Supplier Requirement
Input volt must be standard sine wave, effective value 380V, frequency 50Hz.
Unbalance degree of 3-phase volt must be no more than 5%.
Power supply
Product type
WP120A
Power supply
3 phase
AC380V/50Hz
Min. capacity
Power network
38.5 KVA
Generator
51.4 KVA
Input volt
protection
Fuse
50 A
Circuit breaker
63 A
Cable size
(cross-section)
Input volt
4 mm2
Output volt
15 mm2
Ground lead
4 mm2
Table 3: Power supply connection
Note: The sizes of fuse and breaker in the table are for reference only.

２４
4. Installation:
This series of cutter is small, light and portable. They will be more convenient when being
placed on the trolleys. Ensure the location where the cutter is to be placed is even.
ACUT series of cutters wire diagram as Figure 5:
Figure 4: Connection Chart for WP series
1. 3-phase 380V power source
2. Gas hose
3. Air compressor
4. Cutting torch
5. Output cable
6. Workpiece
The max gas pressure of optional air compressor should be 0.8 Mpa and gas flow rate be no less
than 250L/min.Connect air compressor to inlet of air gauge on the rear panel of cutter. Turn on air
compressor to let gas pressure climb up to proper value for cutting. Then turn on air switch on the
rear panel of the cutter.

２５
Operating Instruction
1. Functional introduction
1.1 Front panel illustration and parts number reference
Figure 5: Front panel
1. “Gas test / Cutting”switch
Switch to “Gas test”, check if gas flow is normal; to “cutting”to perform air plasma
cutting.
2. “Auto-lock / Non-auto-lock” switch
Switch to “Non-auto-lock”, perform cutting when pressing torch trigger, stop welding
when releasing the trigger. This mode is suitable for short cutting seam. To “Auto-lock”,
after successfully starting arc by pressing torch trigger, then you can perform cutting by
releasing the trigger. When you press torch trigger again, torch will stop cutting. This
mode is suitable for long cutting seam.
3. “Power on / off”indicator
Indicating whether power source is effectively connected to power supply
4. “Protection” indicator lamp
Cutting machine will automatically stop working when it is overheat, and the lamp will
light up.
5. “Welding current” regulation knob
Used to adjust cutting current
6. Cable socket
Connect to workpiece
7. Central socket of cutting machine
Connect to cutting torch

２６
1.2 Rear panel illustration and parts number reference
Figure 6: Rear panel
1. Circuit breaker
The function of circuit breaker is to protect cutting machine by automatic trip to
turn-off power supply while the machine is overloaded or in failure. Normally, the circuit
breaker flipped to upward means power-on. Use switch on the switchboard to start orstop
cutting machine, avoiding using the circuit breaker.
2. Input power cable
It is 4-pin cable. The mixed-colored wire must be firmly grounded, the rest wires
connect to corresponding 3-phase power supply.
3. Compressed air filter
Connect to air compressor by gas hose for reducing gas pressure and filtering moisture
in the air. Adjust the knob to alter the output air pressure of filter, the values of air
pressure displaying at the air gauge are normally in the range of 0.6-0.8Mpa.The water
accumulated in the water trap should not touch on the filter element. Please let out the
accumulated water in time by releasing the valve on the bottom. Otherwise, the
accumulated water will enter the cutting torch, thus influencing arc starting and cutting
performance.
4. Specification plate
5. Cooling fan

２７
Cool down the heat components in the cutting machine.
2. Operating procedure
2.1 After going through periodical check process, power on the cutting machine, then
working indicator will light up and cooling fan will spin.
2.2 Flip the “Gas test/Cutting”switch to “Gas test”.
The gas valve in the machine will turn on and let gas flow up to one minute to remove
condensed water drops accumulating in the torch. Regulate the compressed air filter to
let the hand of air gauge indicate 0.45 Mpa. Then flip the “Gas test/Cutting”switch to
“Cutting”.
2.3 ACUT60 cutting machine applies contact type cutting torch. When cutting, let the
nozzle of torches touch workpiece, then press the torch button to start arc.
ACUT100 andACUT120 cutting machine apply non-contact type cutting torch. When
cutting, keep a distance from 3 to 5 mm between nozzle and workpiece to start arc and
allow no touch between nozzle and workpiece in the process of cutting.
2.4 Usually, cutting begins at the margin of the workpiece. It can also start at any point of the
workpiece, but cutting torch should be tilted a bit to blow molten metal and form the
start point of groove.
2.5 While in cutting, keep cutting torch moving at consistent speed.
2.6 While stopping cutting, move the torch away from woekpiece after the plasma arc goes
out completely. Otherwise the workpiece will be distorted by remained arc.

２８
Repair & Maintenance
WARNING: Have a qualified electrician do the maintenance and trouble shooting work. Turn
the input power off, using the disconnect switch at the fuse box before working
inside the machine.
1. Attentions:
1．When problems such as abnormal cutting seam, arc-interruption, difficult arc-start
occurs, please check easy-worn-out consumables like nozzle or electrode and replace
them if they are bad consumption.
2．When assembly electrode ,gas diffuser, nozzle and nozzle cover, should aware of fitting
up coaxially, nozzle cover press the nozzle toughly.
3．While in cutting, avoid moving cutting torch too quickly in case burning out nozzle due
to arc flame rebounding from non-cut-through workpiece base as well as moving too
slow to influence cutting quality.
4．While in cutting, please keep air pressure in the range of 0.6 to 0.8Mpa. Let out
accumulated water in the compressed air filter timely.
5．The machine equipped with low-voltage protection. The machine will automatic stop
working when the input primary power is too low.
6．The machine equipped with overheat protection. The machine will automatic stop
working when the temperature inside the machine is very high and the protection lamp
on the front panel will light on.

２９
№
Trouble
Causes
What to do
1
Indicator lamp does not
light up and machine does
not work when switched
on.
1)Phase missing
2)Fuse broken（2A）
3)Power cable broken
1)Inspect power source
2)Inspect cooling fan,
transformer for ZKB/QDB,
and main control board
3)Inspect cable
2
Overheat indicator lamp
lights up
1)Too high temperature
inside machine
2)Thermal switch is
damaged
1)Stop working till machine
cools down
2)Change the thermal switch
3
No gas flows out while in
gas test.
1)Electromagnet valve is
damaged
2) Gas way is blocked
3)“Gas test / Cutting”
switch is damaged
4)The output air pressure
of air compressed filter
is too high.
1)Replace
2)Inspect gas way
3) Replace
4)Regulate pressure knob on the
filter to reduce air pressure
and release water valve.
After air pressure get down,
tighten up the valve.
4
The cutting torch’s button
does not work.
1)Button is damaged
2)Wire is broken
3)Control board is
damaged
1)Replace
2)Connect the broken wire
3) Replace
5
Too wide cut
1)Slow cutting speed
2)Nozzle is burn out
1)Increase cutting speed
2)Replace
6
Non-vertical cut
1)Nozzle is burn out
2)Non-alignment of
nozzle to electrode.
3)Tilt cutting torch
1)Replace
2)Align the nozzle and the
electrode
3)Adjust the cutting angle.
Table 4: Trouble Shooting Table