Lokermann Grand tig 400 acdc pulse User manual

USER MANUAL

INVERTER Based Welding Machines

GRAND

TIG 400

ACDC PULSE

IMPORTANT: Read this OPERATOR MANUAL together

with PRESCRIPTION AND COMPLIANCE MANUAL before

to use this equipment. In case of loss one of two parts

contact immediately your dealer.

Allow the operator to consult this manual.

1INSTALLATION WARNING

2OVERVIEW

2.1 Features

2.2 Technical Data

2.3 Brief Introduction

2.4 Duty cycle and Over-heat

2.5 Working Principle

2.6 Volt-Ampere Characteristic

3INSTALLATION & OPERATION

3.1 Layout for the front and rear panel

3.2 Power supply input connection

3.3 Installation & Operation for MMA Welding

3.3.1 Set up installation for MMA Welding

3.3.2 Operation for MMA Welding

3.3.3 MMA Welding Troubleshooting

3.4 Installation & Operation for TIG Welding

3.4.1 Set up installation for TIG Welding

3.4.2 Operation for TIG Welding

3.4.3 Remote current control

3.4.4 Tig Welding Techniques

3.4.5 Electrodes

3.4.6 TIG Welding troubleshooting

3.5 Remote control Configuration

3.5.1 Wireless remote control Configuration

3.5.2 Wire foot pedal Configuration

3.6 Operation environment

3.7 Operation Notices

4 MAINTENANCE & TROUBLESHOOTING

4.1 Maintenance

4.2 Troubleshooting

4.3 List of error code

4.4 Electrical schematic drawing

CONTENT

Installation

warning

INSTALLATION WARNING

This machine is certified according to 60974-10:2014 Arc Welding Equipment Part 10: Electromagnetic

compatibility (EMC) requirement and the EUT belongs to Group 2 Class A.

WARNING: This Class A equipment is intended for industrial use and it is not intended for use in

residential locations where the elctrical power is provided by the public low-voltage supply system.

There may be potential difficulties in ensuring electromagnetic compatibility in those locations, due to

conducted as well as radiated disturbances.

WARNING: This equipment does not comply with IEC 61000-3-12. If it is connected to a public low-

voltage system, it is the responsability of the installer or user of the equipment to ensure, by consultation

with the distribution network operator if necessary, that the equipment may be connected.

Assessment of area

Before installing arc welding equipment the user shall make an assessment of potential

electromagnetic problems in the surrounding area. The following shall be taken into account:

a) other supply cables, control cables, signalling and telephone cables, above, below and

adjacent to the arc welding equipment;

b) radio and television transmitters and receivers;

c) computer and other control equipment;

d) safety critical equipment, for example guarding of industrial equipment;

e) the health of the people around, for example the use of pacemakers and hearing aids;

f) equipment used for calibration or measurement;

g) the immunity of other equipment in the environment. The user shall ensure that other

equipment being used in the environment is compatible. This may require additional

protection measures;

h) the time of day that welding or other activities are to be carried out.

The size of the surrounding area to be considered will depend on the structure of the building

and other activities that are taking place. The surrounding area may extend beyond the

boundaries of the premises.

Methods of reducing emissions-Public supply system

Arc welding equipment should be connected to the public supply system according to this manual

recommendations. If interference occurs, it may be necessary to takeadditional precautions such as

filtering of the public supply system. Consideration should be given to shielding the supply cable of

permanently installed arc welding equipment, in metallic conduit or equivalent. Shielding should be

electrically continuous throughout its length. The shielding should be connected to the welding power

source so that good electrical contact is maintained between the conduit and the welding power

source enclosure.

Maintenance of the arc welding equipment

The arc welding equipment should be routinely maintained according to this manual

recommendations. All access and service doors and covers should be closed and properly

fastened when the arc welding equipment is in operation. The arc welding equipment should

not be modified in any way, except for those changes and adjustments covered in this manaul. In

particular, the spark gaps of arc striking and stabilising devices

should be adjusted and maintained according to our recommendations.

Welding cables

The welding cables should be kept as short as possible and should be positioned close

together, running at or close to the floor level.

Equipotential bonding

Bonding of all metallic objects in the surrounding area should be considered. However,

metallic objects bonded to the work piece will increase the risk that the operator could receive

an electric shock by touching these metallic objects and the electrode at the same time. The

operator should be insulated from all such bonded metallic objects.

Earthing of the workpiece

Where the workpiece is not bonded to earth for electrical safety, nor connected to earth

because of its size and position, for example, ship’s hull or building steelwork, a connection

bonding the workpiece to earth may reduce emissions in some, but not all instances. Care should be

taken to prevent the earthing of the workpiece increasing the risk of injury to users or damage to other

electrical equipment. Where necessary, the connection of the workpiece to earth should be made by

a direct connection to the workpiece, but in some countries where direct connection is not permitted,

the bonding should be achieved by suitable capacitance, selected according to national regulations.

Screening and shielding

Selective screening and shielding of other cables and equipment in the surrounding area may

alleviate problems of interference. Screening of the entire welding area may be considered for

special applications.

GRAND

TIG 400

ACDC PULSE

Overview

2.1

Features

� IGBT module inverter technology for smooth & stable output, increased reliability and high

duty cycle.

� Phase loss protection for automatic shut down if power supply phase loss occurs,

to prevent damage.

� Integrated heavy duty industrial trolley and water cooler (optional).

� Lift TIG and HF start modes for versatility when welding around sensitive electronic equipment.

� Adjustable arc force, hot start & anti stick control for greater control and ease of use when

MMA welding.

� Electronic HF TIG arc ignition system for contamination free and easy arc starting with low

EMF interference.

� 2T/4T trigger control.

� AC waveforms include square wave, sine wave, triangular wave.

� AC balance control monitors the oxide and helps better cleaning during aluminum welding

� Dual digital display meters for accurate pre- setting and feedback of welding parameters &

output.

� Up/ Down Button Remote Control on torch. (optional)

� Wireless Remote Control and Wire / Wireless Foot Pedal. (optional)

2.2

Technical

Data

Models

Parameters

GRAND TIG 400 AC

DC PULSE

Power Supply Voltage (V) 3~380V/400V/440V±10%

Frequency(HZ) 50/60

Rated input current

(I1max)（A）

36.5 AC MMA

39.5 DC MMA

28.5 AC TIG

31.5 DC TIG

Rated input power

（KW）

16 AC MMA

17.4 DC MMA

12 AC TIG

13 DC TIG

No Load Voltage(V)

58.5

Duty cycle (40℃10 min)

60% 400A

100% 310A

Welding Current Range

（

）

10-400

Up slope/Down slope (S) 0-10

Pre/Post Flow (S) 0.1-2/0-10

Pulse frequency (HZ) 0.5-200

Pulse width range (%) 5-95

AC frequency（HZ）50～250

Clearance effect （%）AC

TIG

15～50

Efficiency(%) ≥85%

Insulation class H

Protection class IP23

Cooling AF

Net Weight(Kg) 28

Dimensions(mm) 640*280*460

2.3

Brief

Introduction GRAND TIG 400 AC DC PULSE adopts the latest Pulse Width Modulation (PWM) technology and the

Insulated Gate Bipolar Transistor (IGBT) power modules. It uses switching frequencies in the

20KHz-50KHz ranges so as to replace the traditional line-frequency transformer type welding machines.

Thus, machines are characterized with portability, small size, lightweight, low energy consumption

and noise, etc.

The parameters of the machine on the front panel all can be adjusted continuously and steplessly,

such as start current, crater arc current, welding current, base current, duty ratio, upslope time,

downslope time, pre-gas, post-gas, pulse frequency, AC frequency, balance, hot start, arc force and

arc length etc. When welding, it takes high frequency and high voltage for arc igniting to ensure the

success ratio of igniting arc.

GRAND TIG 400 AC DC PULSE Characteristics�

�MCU control system, responds immediately to any changes.

�High frequency and high voltage for arc igniting to ensure the success ratio of igniting arc, the

reverse polarity ignition ensures good ignition behavior in TIG-AC welding.

�Avoid AC arc-break with special means, even if arc-break occurs the HF will keep the arc stable.

�Pedal control the welding current.

�TIG/DC operation,If the tungesten electrode touches the workpiece when welding, the current will

drop to short-circuit current to protect tungsten.

�Intelligent protection: over-voltage, over-current, over-heat, when the problems listed before

occurred, the alarm lamp on the front panel will be on and the output current will be cut off. It

can self-protect and prolong the using life.

�Double purposes: AC inverter TIG/MMA and DC inverter TIG/MMA, Excellent performance on

Aluminium-alloy, carbon steel, stainless steel, titanium.

According to choosing the front panel functions, the following six welding ways can be realized.

- DC MMA

- DC TIG

- DC Pulse TIG

- AC MMA

- AC TIG

- AC Pulse TIG

1. For DC MMA, polarity connection can be chosen according to different electrodes,

please refer to 3.3.1.

2. For AC MMA, magnetic flow caused by invariable DC polarity can be avoided.

3. For DC TIG, DCEP is used normally (workpiece connected to positive polarity, while torch connected

to negative polarity). This connection has many characters, such as stable welding arc, low

tungsten pole loss, more welding current, narrow and deep weld;

4. For AC TIG (rectangle wave), arc is more stable than Sine AC TIG. At the same time, you can not

only obtain the max penetration and the min tungsten pole loss, but also obtain better clearance

effect.

5. DC Pulsed TIG has the following characters: 1) Pulse heating. Metal in Molten pool has short time on

high temperature status and freezes quickly, which can reduce the possibility to produce hot crack

of the materials with thermal sensitivity. 2) The workpiece gets little heat. Arc energy is focused.

Be suitable for thin sheet and super thin sheet welding. 3) Exactly control heat input and the size of

the molten pool. The depth of penetration is even. Be suitable for welding by one side and forming

by two sides and all position welding for pipe. 4) High frequency arc can make metal for microlite

fabric, eliminate blowhole and improve the mechanical performance of the joint. 5) High frequency

arc is suitable for high welding speed to improve the productivity.

The letter “X” stands for Duty Cycle, which is defined as the portion of the time a welding machine

can weld continuously with it’s rated output current within a certain time cycle (10 minutes).

The relation between the duty cycle “X” and the output welding current “I” is shown as the right figure.

If the welding machine is overheating, the IGBT over-heat protection sensing will send a signal to the

welding machine control unit to cut the output welding current OFF and light the over-heat pilot lamp

on the front panel. In that case, the machine should not be welding for 10-15 minutes to cool down

with the fanrunning. When operating the machine again, the welding output current or the duty

cycle should be reduced.

2.4

Duty

cycle and

Over-heat

Relation of welding current and

duty cycle for GRAND TIG 400

AC DC PULSE

2.5

Working

Principle The working principle of GRAND TIG is shown as the following figure. Three-phase 380V work frequency

AC is rectified into DC, then is converted to medium frequency AC by inverter device (IGBT module),

after reducing voltage by medium transformer (the main transformer) and rectifying by medium

frequency rectifier (fast recovery diodes), then is outputted DC or AC by selecting IGBT module. The

circuit adopts current feedback control 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

DC AC DC

AC DC

380V,50HZ

Three-phases AC

2.6

Volt-Ampere

Characteristic

TIG series of welding machines has excellent volt-ampere characteristic. Referring to the following

graph. In TIG welding, the relation between the rated loading voltage U2 and welding current I2 is

as follows:

When I2≤600A，U2＝10＋0.04 I2（V）； When I2＞600A，U2＝34（V）.

（1）“-” Output terminal.

（2）TIG torch remote connection socket. *

（3）TIG torch gas connector.

（4）“+” Output terminal.

（5）Inlet gas connector.

（6）Water cooler remote connection socket.

（7）Input power cable.

（8）Power switch Control Panel

（9）LH multifunction display.*

（10）RH multifunction display.*

（11）Power indicator .

（12）Water cooling system error indicator.*

（13）Alarm indicator. *

（14） Water /air cooling selection button.*

（15）Air cooling mode indicator

（16）Water cooling mode indicator

（17）2T trigger mode indicator. *

（18）4T trigger mode indicator. *

（19）MMA hot start setting Indicator. *

（20）MMA welding current setting Indicator.

（21）MMA arc force setting Indicator. *

（22） 2T/4Ttrigger mode selector button

（23）TIG parameter setting indicator. *

（24） Parameter select/adjust Knob. *

（25）Welding current mode selection button

（26）DC wave output indicator. *

（27）AC triangle wave output indicator. *

（28）AC sine wave output indicator. *

（29）AC advanced square wave output indicator. *

（30）MMA mode indicator .

（31）Lift TIG mode indicator. *

（32）Hf TIG mode indicator. *

（33）Welding mode selection button

*Denotes more detailed explanation of function to follow.

Further Controls Explained

LH Digital Multifunction Display (9)

Before welding this displays the setting selected or being adjusted using the control knob (24). During

welding it displays welding current. The parameter setting displayed is indicated by the LEDs beside

the display; Current (A), Saved Setting (JOB), Time (S), Percentage (%) and Frequency (Hz). If left

inactive for several seconds, display will revert back to main welding current setting.

RH Digital Multifunction Display (10)

Before welding this displays secondary functions and error codes. During welding it displays welding

voltage.

Multifunction Smart Control Knob (24)

Press knob to navigate through the control panel parameters not controlled by specific selector

buttons. Parameter/setting selected will be indicated by the LED on the control panel and the value

shown on the LH display (9). Adjust the parameter by turning the knob. Access the job/program

store/ recall function by pressing and holding the knob.

Water Cooling System Error Indicator (12)

When using the integrated water cooler, the system is equipped with a pressure sensor. If the coolant

pressure is insufficient, this indicator will light and the welding output will not be able to be active, in

order to protect the torch and cooling system.

Alarm Indicator (13)

Lights when over voltage, over current, input phase loss or electrical overheating (due to exceeding

duty cycle) is detected and protection is activated. When protection is activated, welding output will

be disabled until the safety system senses the overload has reduced sufficiently and indicator lamp

goes out. May also trigger if machine experiences an internal power circuit failure.

Installation

Operation

3.1

Layout for

the front

and rear

panel

2.4

Duty

cycle and

Over-heat

Water / Air Cooling Selection Button (14)

When using the integrated water cooling system with a water cooled torch, select the ‘water’ option

(16). This will activate the water cooler power (the water cooler must also be switched on the rear

panel) and the water cooling protection system. If using air cooled torch, select ‘Air’ option (15).

Note the welding machine comes standard with a water cooled torch system. Operating a water

cooled torch without water cooling will quickly cause serious damage to the torch. Damage to torch

or components due to lack of water is not covered under machine warranty.

MMA settings

Hot start (19)

Hot start provides extra power when the weld starts to counteract the high resistance of the electrode

and workpiece as the arc is started. setting range (0-10).

Arc force (21)

An MMA welding power source is designed to produce constant output current (CC).This means

with different types of electrode and arc length; the welding voltage varies to keep the current

constant. This can cause instability in some welding conditions as MMA welding electrodes will have

a minimum voltage they can operate with and still have a stable arc.

Arc Force control boosts the welding power if its senses the welding voltage is getting too low. The

higher the arc force adjustment, the higher the minimum voltage that the power source will allow.

This effect will also cause the welding current to increase. 0 is Arc Force off, 10 is maximum Arc Force.

This is practically useful for electrode types that have a higher operating voltage requirement or joint

types that require a short arc length such as out of position welds.

TIG settings

TIG 2T/4T Trigger Control

2T Mode (17)

The trigger is pulled and held on to activate the welding circuit, when the trigger is released, the

welding circuit stops.

4T Mode (18)

This is known as ’latching’ mode. The trigger is pulled once and released to activate the welding

circuit, pulled and released again to stops the welding circuit. This function is useful to longer welds as

the trigger is not required to be held on continuously. TIG series of welding machines also has more

current control options that can be used in 4T mode.

TIG Parameter Setting (23)

Pre gas flow setting indicator (1)

Pre-flow controls the period shielding gas will flow for when the torch is triggered before the arc starts.

This purges the work area of atmospheric gas which could contaminate the weld before the weld

starts. Unit(S) and setting range (0.1-2S).

Start current setting indicator (2)

Available in 4T trigger mode, sets a welding current 10-100% of the main welding current activated

when the trigger is held on to ‘latch’ the trigger before the main weld current is started. Once the

trigger is released, the current will go through the upslope (3) period if it is set, to the main welding

current (4).

Up slope setting indicator (3)

When the trigger is activated, the welding current will increase gradually over the time selected

up to the set main welding current (4). Unit(S) and setting range (0-10.0S).

TIG welding current setting indicator (4)

Sets the main welding current. Unit(A) and setting range (10-320A/400A/500A).

Base current setting indicator (5)

Only available when pulse mode (12) is selected. Sets the current of the low/ base pulse. Unit(A)

and setting range (10-320A/400A/500A).

Down slope setting indicator (6)

When the trigger is released, the welding current will reduce gradually over the time selected down

to 0. This allows the operator to complete the weld without leaving a ‘crater’ at the end of the weld

pool. Unit(S) and setting range (0-10.0S).

End current setting indicator (7)

Available in 4T trigger mode only, sets a welding current 10-100% of the main welding current

activated when the trigger is held on to ‘unlatch’ the trigger before the weld is finished. If

downslope (6) is set, the current will go through the downslope period before going to the end

current set. When the trigger is released, the arc will stop.

Post gasflow setting indicator (8)

Controls the period of time the shielding gas continues to flow for after the arc is stopped. This

protects the weld area and torch tungsten from contamination while it is still hot enough to react with

atmospheric gases, after the weld is finished. Unit(S) and setting range (0-10.0S).

Pulse width setting indicator (9)

Only available when pulse mode (12) is selected. Sets the time proportion as a percentage between

the peak current and base current when using pulse mode. Neutral setting is 50%, the time period of

the peak current and base current pulse is equal. Higher pulse duty setting will give greater heat

input, while lower pulse duty will have the opposite effect. Unit(%) and setting range (5-95%).

Pulse frequency setting indicator (10)

Only available when pulse mode (12) is selected. Sets the rate that the welding output alternates

between the peak and base current settings. Unit(Hz) and setting range (0.5-999Hz).

Pulse mode ‘off’ indicator (11)

Pulse mode ‘On’ indicator (12)

Clean Width Area/ AC Balance Adjustment (13)

Only available in AC welding mode (27,28,29). Adjusts the balance as a percentage between the

forward and reverse current cycles when welding in AC output mode. The reverse part of the AC

cycle gives the ‘cleaning’ effect on the weld material, while the forward cycle melts the weld

material. Neutral setting is 0. Increased reverse cycle bias will give greater cleaning effect, less weld

penetration and more heat in the torch tungsten, which gives the disadvantage of reducing the

output current that can be used for a given tungsten size, to prevent the tungsten overheating.

Increased forward cycle bias will give the opposite effect, less cleaning effect, greater weld

penetration and less heat in the tungsten.

For maximum effectiveness, ideally the clean width/ AC balance should be set with as much forward

cycle bias as possible, while still maintaining a sufficient level of oxidisation removal for a

contamination free weld pool. The cleaner non-ferrous metal is before welding, the more effective it

is to weld. This effect can also be used to reduce heat in the tungsten, allowing use of a pointed

tungsten tip shape for a more defined arc. setting range (-5-+5).

AC Frequency Adjustment (14)

Only available in AC welding mode (27,28,29). Increasing AC frequency will focus the shape of the

arc, resulting in a tighter, more controlled arc causing increased penetration and less heated

affected area for the same current setting. Slower frequency will result in a wider, softer arc shape.

Unit(Hz) and setting range (50-250Hz).

AC/DC Output Modes

DC (Direct Current) Welding Output (26)

Suitable for TIG welding ferrous (iron based) metals such as mild steel and stainless steel, copper and

titanium. TIG welding reactive metals such as Aluminium, Magnesium and Zinc requires AC

(alternating current) output. When reactive metals are exposed to air they form an oxide layer that

insulates the base metal and prevents welding current flowing, it also contaminates the weld pool.

Reverse current flow is required to break through/ clean off this oxide layer so that welding can take

place, while the current flow during the positive cycle does the majority of the heating of the

weld pool area.

AC Triangle Wave Welding Output (27)

Reduced heat input for same current setting. Especially useful for welding thin metal.

AC Square Wave (28)

Focused arc for maximum penetration, fast travel speed with best directional control.

AC Sine Wave Welding Output (29)

Traditional AC TIG welding wave form. Quieter, ‘soft’ arc characteristic.

TIG Arc Starting Modes

TIG HF/ Lift Ignition Modes (31,32)

For TIGwelding process,contactof the torch tungsten to the workpiece will cause contamination of

the tungsten and the workpiece that will adversely affect the weld quality, especially when the

tungsten is electrically energised.

HF Ignition (High Frequency) sends a pulse of high energy electricity through the torch system that is

capable of ‘jumping’ between the tungsten and the workpiece, ensuring arc starting without any

contact between the tungsten and workpiece. The disadvantage of HF ignition is that the high ener-

gy electrical pulse creates significant electrical and radio signal interference, which limits its use

around sensitive electronic equipment such as computers.

Lift TIG Ignition is a compromise that minimises tungsten contamination while eliminating the electrical

interference of HF start systems. Lift arc starting works by lightly resting the tungsten on the work piece,

activating the torch trigger signal and then lifting the tungsten off. The control circuit will sense when

the tungsten is removed from the work piece and send a low powered pulse of electricity through the

tungsten that will cause the TIG arc to initiate. Because the tungsten is not ‘live’ when it is in contact

with the work, contamination is minimised.

Program/Job Memory

The welding machine has 9 memory/ job spaces that parameters can be saved to for easy recall.

To access a saved program, press and hold in the control knob (24) and the program number 1-9 will

show on the display, the ‘JOB’ indicator will be lit. Adjust to the program number required by rotating

the control knob. Once the program is accessed, it will automatically load. To return to normal

parameter settings, press the control knob again (which will also load the selected program) To save

parameters set as a program, press and hold the control knob for a few seconds and the display will

blink. The settings are now saved in the last program space that was selected. If setting parameters to

save as a program, ensure that you start with a program number that the data is OK to overwrite, as

the previous settings saved to that memory space will be lost.

Pulse welding

Pulse welding mode switches the welding output between a high and low current output in a cyclical

manner. When used correctly this function has substantial benefits in the TIG welding process including

greater weld penetration for less work heat input and greater control of the weld pool.

The basic theory for setting the base current using pulse mode is that the base current should be

sufficient to maintain the existing molten weld pool, while the peak current is sufficient to melt new

metal in order to move/ expand the molten weld pool. Increased pulse frequency will have the effect

of making the arc more tightly focused which is useful for fine stainless work and similar.

Pulsing can also be used to help move the weld pool, this technique is useful for welding out of position

or with materials that have higher viscosity weld pool. Higher pulse duty setting will give greater heat

input, while lower pulse duty will have the opposite effect.

Water Cooling

The welding machine ca ne supplied with the integrated water cooler. The correct coolant to use is a

mixture of Mono Propylene Glycol and water in a 1:3 ratio (25% propylene glycol. Pure water may

be used as a coolant liquid, though it is not recommended for the long term reliability of the water

cooling system as it does not have the lubrication properties of glycol and does not provide protection

against freezing. Ready to use coolant fluid can be purchased from authorised Strata dealers.

Do not operate a water cooled torch without the cooling system operating!