Würth POWERCUT 70 User manual

PLASMA CUTTING MACHINE
APARAT ZA PLAZMA REZANJE
POWERCUT 70
Art. 5952 899070
Operating instructions
Uputstvo za upotrebu
Uputstvo za upotrebu
Uputstvo za upotrebu

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PLASMA CUTTING MACHINE
POWERCUT 70
General safety rules
WARNING: Read and understand all instructions. Failure to follow all instructions
listed below may result in serious injury.
CAUTION: Do not allow persons to operate or assemble this POWERCUT 70
until they have read this manual and have developed a thorough understanding of how
the POWERCUT 70 works.
WARNING: The warnings, cautions, and instructions discussed in this instruction
manual cannot cover all possible conditions or situations that could occur. It must be
understood by the operator that common sense and caution are factors which cannot
be built into this product, but must be supplied by the operator.
SAVE THESE INSTRUCTIONS
IMPORTANT SAFETY CONSIDERATIONS
1.1 Your Welding Environment
-Keep the environment you will be welding in free from flammable materials.
-Always keep a fire extinguisher accessible to your welding environment.
-Always have a qualified person install and operate this equipment.
-Make sure the area is clean, dry and ventilated. Do not operate the welder in humid,
wet or poorly ventilated areas.
-Always have your welder maintained by a qualified technician in accordance with local,
state and national codes.
-Always be aware of your work environment. Be sure to keep other people, especially
children, away from you while welding.
-Keep harmful arc rays shielded from the view of others.
-Mount the welder on a secure bench or cart that will keep the welder secure and
prevent it from tipping over or falling.
G
B

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1.2 Your Welder’s Condition
-Check ground cable, power cord and welding cable to be sure the insulation is not
damaged. Always replace or repair damaged components before using the welder.
-Check all components to ensure they are clean and in good operating condition before
use.
1.3 Use of Your Welder
CAUTION
Do not operate the welder if the output cable, electrode, torch, wire or wire feed system
is wet. Do not immerse them in water. These components and the welder must be
completely dry before attempting to use them.
-Follow the instructions in this manual.
-Keep welder in the off position when not in use.
-Connect ground lead as close to the area being welded as possible to ensure a good
ground.
-Do not weld if you are in an awkward position. Always have a secure stance while
welding to prevent accidents. Wear a safety harness if working above ground.
-Do not drape cables over or around your body.
-Wear a full coverage helmet with appropriate shade (see ANSI Z87.1 safety standard)
and safety glasses while welding.
-Wear proper gloves and protective clothing to prevent your skin from being exposed to
hot metals, UV and IR rays.
-Do not overuse or overheat your welder. Allow proper cooling time between duty
cycles.
-Keep hands and fingers away from moving parts and stay away from the drive rolls.
-Do not point torch at any body part of yourself or anyone else.
-Always use this welder in the rated duty cycle to prevent excessive heat and failure.
1.4 Specific Areas of Danger, Caution or Warning
Electrical Shock
WARNING
Electric arc welders can produce a shock that can cause injury or death.
Touching electrically live parts can cause fatal shocks and severe burns.
While welding, all metal components connected to the wire are electrically hot.

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Poor ground connections are a hazard, so secure the ground lead before welding.
-Wear dry protective apparel: coat, shirt, gloves and insulated footwear.
-Insulate yourself from the work piece. Avoid contacting the work piece or ground.
-Do not attempt to repair or maintain the welder while the power is on.
-Inspect all cables and cords for any exposed wire and replace immediately if found.
-Use only recommended replacement cables and cords.
-Always attach ground clamp to the work piece or work table as close to the weld area
as possible.
-Do not touch the welding wire and the ground or grounded work piece at the same
time.
-Do not use a welder to thaw frozen pipes.
Fumes and Gases
WARNING
-Fumes emitted from the welding process displace clean air and can result in injury or
death.
-Do not breathe in fumes emitted by the welding process. Make sure your breathing air is
clean and safe.
-Work only in a well-ventilated area or use a ventilation device to remove welding
fumes from the environment where you will be working.
-Do not weld on coated materials (galvanized, cadmium plated or containing zinc,
mercury or barium). They will emit harmful fumes that are dangerous to breathe. If
necessary use a ventilator, respirator with air supply or remove the coating from the
material in the weld area.
-The fumes emitted from some metals when heated are extremely toxic. Refer to the
material safety data sheet for the manufacturer’s instructions.
-Do not weld near materials that will emit toxic fumes when heated. Vapors from
cleaners, sprays and degreasers can be highly toxic when heated.
UV and IR Arc Rays
DANGER .
The welding arc produces ultraviolet (UV) and infrared (IR) rays that can
cause injury to your eyes and skin. Do not look at the welding/cutting arc without
proper eye protection.

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-Always use a helmet that covers your full face from the neck to top of head and to the
back of each ear.
-Use a lens that meets ANSI standards and safety glasses. For welders under 160
Amps output, use a shade 10 lens; for above 160 Amps, use a shade 12. Refer to the
ANSI standard Z87.1 for more information.
-Cover all bare skin areas exposed to the arc with protective clothing and shoes.
Flame-retardant cloth or leather shirts, coats, pants or coveralls are available for
protection.
-Use screens or other barriers to protect other people from the arc rays emitted from
your welding.
-Warn people in your welding area when you are going to strike an arc so they can
protect themselves.
Fire Hazards
WARNING
Do not weld on containers or pipes that contain or have had flammable,
gaseous or liquid combustibles in them. Welding creates sparks and heat that can
ignite flammable and explosive materials.
-Do not operate any electric arc welder in areas where flammable or explosive
materials are present.
-Remove all flammable materials within 10 m of the welding arc. If removal is not
possible, tightly cover them with fireproof covers.
-Take precautions to ensure that flying sparks do not cause fires or explosions in
hidden areas, cracks or areas you cannot see.
-Keep a fire extinguisher close in the case of fire.
-Wear garments that are oil-free with no pockets or cuffs that will collect sparks.
-Do not have on your person any items that are combustible, such as lighters or
matches.
-Keep work lead connected as close to the weld area as possible to prevent any
unknown, unintended paths of electrical current from causing electrical shock and fire
hazards.
-To prevent any unintended arcs, cut wire back to 6 mm stick out after welding.

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Hot Materials
CAUTION
Welded materials are hot and can cause severe burns if handled improperly.
-Do not touch CUTTING materials with bare hands.
-Do not touch torch nozzle after welding until it has had time to cool down.
Sparks/Flying Debris
CAUTION
Welding creates hot sparks that can cause injury. Chipping slag off welds
creates flying debris.
-Wear protective apparel at all times: ANSI-approved safety glasses or shield, welder’s
hat and ear plugs to keep sparks out of ears and hair.
Electromagnetic Field
CAUTION
-Electromagnetic fields can interfere with various electrical and electronic
devices such as pacemakers.
-Consult your doctor before using any electric arc welder or cutting device
-Keep people with pacemakers away from your welding area when welding.
-Do not wrap cable around your body while welding.
-Wrap Cutting torch and ground cable together whenever possible.
-Keep Cutting torch and ground cables on the same side of your body.
Shielding Gas Cylinders Can Explode
WARNING
-High pressure cylinders can explode if damaged, so treat them carefully.
-Never expose cylinders to high heat, sparks, open flames, mechanical shocks or arcs.
-Do not touch cylinder with Cutting torch.
-Always secure cylinder upright to a cart or stationary object.
-Keep cylinders away from welding or electrical circuits.
-Use the proper regulators, gas hose and fittings for the specific application.

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-Do not look into the valve when opening it.
-Use protective cylinder cap whenever possible.
1.5 Proper Care, Maintenance and Repair
DANGER .
-Always have power disconnected when working on internal components.
-Do not touch or handle PC board without being properly grounded with a wrist strap.
Put PC board in static proof bag to move or ship.
-Do not put hands or fingers near moving parts such as drive rolls of fan.
POWERCUT 70 use and care
- Do not modify the POWERCUT 70 in any way. Unauthorized modification may impair
the function and/or safety and could affect the life of the equipment. There are
specific applications for which the POWERCUT 70 was designed.
- Always check of damaged or worn out parts before using the POWERCUT 70.
Broken parts will affect the POWERCUT 70 operation. Replace or repair damaged or
worn parts immediately.
- Store idle POWERCUT 70. When POWERCUT 70 is notin use, store it in a secure
place out of the reach of children. Inspect it for good working condition prior to
storage and before re-use.

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Product Introduction
POWERCUT series is metal cutter equipment with high efficiency. Its working principle
is to use the compressed air as the ionization medium, and then form the high density
plasma arc heat source by the torch nozzle’s compress effect, which melt the metal as
a result. The melted metal will be blown off by the high speed gas flow at the same time
to form into narrow cutting slot, thus the metal can be melted and cut very rapidly.
This series cutting equipment possesses good features like easy operation, energy
saving, high speed cutting, narrow cutting slot, less deformation of work pieces, reliable
and safe apply, low investment etc. It is suitable for almost all metal plate and pipe
materials, including mild steel, stainless steel, aluminum, copper, titanium, nickel alloy,
cast iron etc. It is widely used in ship building, motor manufacturing, metal structure,
boiler, pressure vessel and pipe making, medical appliance and machinery making etc.
The feature of POWERCUT series:
- Small and light ,the weight of POWERCUT 70 is only 18 kg.
- Advanced IGBT inverter technology attributes to stable capability ,high efficiency and
energy saving
- Work can be reliable at ±15% of fluctuation for input voltage.
- Visible gas adjustment and easy operation, specially suitable for decoration。
- Cutting thickness capacity of machine will reach 22 mm.
- Cutting slot both narrow and glabrous;no damage to the work pieces.
- Complete protective function. include the protections of overheat.

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Safety Operation
Operator’s Self Protection
●Please always follow the rules that conform to safety and hygiene. Wear protective
garments to avoid injuries to eyes and skins
●Do not touch to the working piece while operation in case of the electric leaking
accident occurred
●Do not touch to the two output polarity (The polarity of the torch and the polarity of the
work piece.) at the same time without any insulation protection.
●Do not cut the vessel with inflammable and explosive materials or the sealed
pressure vessel.
●Avoid operation under water or high humidity places.
●Shut off the power supply before changing the connect tip or electrode.
●Do not aim the torch at any part of the body.
●Do not aim the contact part of the torch after the cutter is on.
Attention
●POWERCUT 70 series cutter is electronic products whose spare parts are very
tender, do not change or adjust with a rush otherwise the connections will be
damaged.
●Check the connection to see if it is well connected, whether the earth (ground)
connection is reliable, etc.
●Fumes and gases produced when cutting are hazardous to health. Make sure to work
in places where there are exhaust or ventilation facilities to keep fumes or emissions
away from the breathing zone.
●Insulate the working area since spatter will be occurred.
●No access to switching or modulating by others while the cutter is working
●Cutters have strong electromagnetism and frequency interference, so keep away
people with heart pace or the articles which can be interfered by electromagnetism
and frequency.
●No squeeze or punch to the cutting cable.

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●Never clean the slag in the torch head by violent knocking.
●The puckering angle of the torch cable can not be too small, otherwise the inside
cable of gas pipe will be damaged which can result into accident.
●Never allow anybody else other than the operator himself to access the job site.
●No touching on the output connection or any other electrification parts while
welding/cutting.
Safety Measures to Be Taken To Assure the Correct Installation and Position
●Precaution must be taken to keep the operator and the machine from the foreign
materials falling from up above
●The dust, acid and erosible dirt in the air at the job site must not exceed the amount
required by the norm (excluding the emission from the cutter).
●The cutting machine must be installed in the place where it must not be exposed to
sun and rain. Also it must be stored in less humid place with the temperature range at
-10～+40℃.
●There should be 50 cm space left for the cutting machine to have good ventilation.
●Make sure that there is no metal-like foreign body to enter the cutting machine.
●No violent vibration in the cutter’s surrounding area.
●Make sure the machine is installed in where it won’t interfere the surrounding
electromagnetism equipment during the operation.
●Take measures to prevent wind while operating since the cutter is gas shielded.
Safety Check
Each item listed below must be carefully checked before operation:
●Make sure that the cutting machine has reliable earth connection.
●Make sure that there is always sound output and input wire connection instead of
exposing outside.
Regular check needs to be conducted by the qualified personnel after the cutter has
been installed over a period of six months, which involves as follows:
●Routine cleaning is required to make sure there is no abnormal condition happening
in the tightened places such as loose and slipped magnetic core.

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●The external parts installed on the cutter’s panel must guarantee that the welder
works properly.
●Cutter torch must be replaced is it worn out.
●If Any damage occur to the input cable it should be dealt safely.
●Make sure whether there is enough power supply to make the cutting machine work
properly, and the power supply connected into the cutter should be equipped with
safety protection device.
Notice: Cut off the power supply before opening the case to check.
Please do not hesitate to contact us for technical assistance whenever you come
across the problems you can not work out or you may deem difficult to fix.

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Technical Specifications
Environment for the Product
●The surrounding temperature range:
When cutting: -10～+40℃
During transport or in storage: -25～+55℃
●Relative humidity:
When at 40°C: ≤50%
When at 20°C: ≤90%
●The dust, acid and erosible materials in the air must not exceed the amount required
by the norm (apart from the emissions from the cutter). No violent vibration at the job
site.
●Keep from raining when it is used outdoor.
Keep from raining when it is used outdoor
●The voltage oscillogram should display actual sine wave.
●The oscillation of the supplied voltage should not exceed ±15% of the rated value.
●The imbalance rate of three phases main supply should not be less than 0.5%.
●Frequency fluctuation should be less than ±2%.
Theory of Cutting Machine (see the principle chart)
POWERCUT Series Air POWERCUT 70 is high speed cutting equipment with
advanced technology which is using high density plasma arc as source of the heat. The
plasma arc would be acquired by the compressed air as ionization medium and the
compression of the torch’s nozzle.
Cutter’s Structure
POWERCUT 70 applies portable box structure: digital display, protect indictor light, the
cutting current adjust knob,are installed on the first half of the front board; and the
current output ‘+’ electrode quick connector, ‘-’ electrode quick connector, cutting torch
control (two pins socket), switch socket are installed on the second half; the power inlet.

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Impressed gas input connector and power switch, are installed on the back board; the
control transformer,control press circuitry board can be seen on the first installation
board after shelling the out case; the rectification bridge etc. are installed on the
bottom, the medium frequency transformer, fast recovery rectifiers, heat sink etc. are
installed in the centre of the box.

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Main Technical Data
Items
Unit
POWERCUT 70
Rated input voltage
V
400
Power supply frequency
Hz
50/60
Phase
PH.
3
Rated input capacitance
KVA
7.9
Rated input current
A
12.5
Output non-load voltage
V
330
Rated operation voltage
V
104
Output Current
A
25-70
Gas flow
L/min
300
Air pressure
MPa
0.3～0.6
Lag gas time
S
5～15
Max cutting thickness
mm
22
Rated duty cycle
%
60
Cooling type
Fan-cooled
Arc start type
High-frequency transfer arc
Insulation grade
grade
H
Case Protection Class
IP
IP21S
Weight
kg
18
Dimension (L*W*H)
mm
505×240×404
Applying Norm of Cutter
POWERCUT 70 conforms with the following standard to perform:
●EN 60974-1
Installation & Maintenance of the Torch & Replacement of the Spare Parts
Please notice: Please make sure the power supply switch is off before
loading/unloading the cutting torch and replacing the spare parts.

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●The installation of the torch’s spare parts should follow the order according to the
pictures listed blow. Please notice during the installation: the distributor should not be
installed in reverse, and the protection cover should be screwed tightly, but please be
alert that over pressure would smash the distributor.
●When the nozzle’s hub hole is burnt to a degree that it will affect the cutting slot, it
should be replaced in time
●The electrode should be replaced in time when it is worn down or be shortened to
about 2mm, otherwise the torch will be broken. (See the following pictures.)
Pt.No
Description
Pt.No
Description
1
Torch head
3
Protect ring
4
Electrode
5
Tip
7
Ceramic nozzle
8
Carriage
9
Handle
12
Rubber hose
13
Air-power cable
15
Trigger wire connector

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Cutting Torch Assemble Sketch
●If there are any spare part s or the distributor are broken, they should be replaced in
time.
●The torch’s cable, working gas pipe, protection cover or the wire are broken, then
they should be replace in time.
Remark of Illustration
Ground
Descending
Plasma Cutting
Power Source & AC 1 Phases
3Phases Arc Welding transformer -- Rectifier
DC
X：Duty Cycle
I1：Rated Input Current
I2：Rated Cutting Current
P1：Rated Input Power
U0：Rated Open Circuit Voltage
U1：Rated Input Voltage
U2：Rated Load Voltage
～50Hz：AC, Rated Frequency 50Hz
...V：Unit of Voltage
...A：Unit of Current
...KVA：Unit of Power
...%：Unit of Duty Cycle
...A/...V：Cutting Current and Relevent Load Voltage
...MPa：Unit of Pressure
….bar：Unit of Pressure
EN60974-1：Safety standard for the welding equipment
~
3

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IP21S：Grade for the case protection. IP is the code of International
Protection. 2 mean preventing user’s finger from the
dangerous parts; preventing the solid material with the
diameter no less than 12.5mm into the box. 1 means
preventing water dropping vertically which is harmless. S
means water proof test is conducting while the movable part is
standstill.
H：H insulation grade

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Installation
Cutter’s Placement
●The dust, acid and erosible dirt in the air at the job site must not exceed the amount
required by the norm.
●The welder must be installed in the place where it must not be exposed to sun and
rain. Also it must be stored in less humid place with the temperature range at -10~+40
°C.
●There should be 50 cm space about for the welding machine to have good ventilation.
●Apparatus to exclude wind and smoke should be equipped if the inside aeration is not
proper.
Cutter’s Placement

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Connection Sketch
Front panel Back panel
1. Digital
ampermeter
2. 2T/4T
3. Gas check
Switch
4. Torch Switch
5. Connector for
Torch“-”
6. Thermal
Indicator Light
7. Gas lacking
Light
8. Cutting Current
knob
9. Post Gas knob
10. Pilot Arc
11. Connector for
Work piece “+”
12. Power
On/Off Switch
13. Power
Input Cable
14. Gas Inlet
Connection between Cutter and Power Supply
●Connect the ‘Power Supply Input Cable’on the back board of the cutter to the single-
phase power supply;
●Connect the ‘Safe Earth Connection Bolt’with the power supply earth cable reliably
with the lead whose cross section area is not less than the cutter’s input lead’s.
Power Supply Configure of one Cutter:
Items
POWERCUT 70
Air switch（A）
≥30
Fuse（A）
25
Knife switch（A）
≥30
Supply cable（mm2）
≥4