The welding circuit contains different materials and cross-sections, as well as contact resistances at the coupling points.

In a series circuit, the resistances add up; large power losses and voltage drops can occur.

The contact resistances at coupling points vary greatly with the contact force and the surface condition.

1. General information about the welding circuit

The welding circuit contains different materials and cross-sections, as well as contact resistances at the coupling points.

In a series circuit, the resistances add up; large power losses and voltage drops can occur.

The contact resistances at coupling points vary greatly with the contact force and the surface condition.

1. General information about the welding circuit
2. Electrical resistance in the welding circuit

The welding circuit contains different materials and cross-sections, as well as contact resistances at the coupling points.

In a series circuit, the resistances add up; large power losses and voltage drops can occur.

The contact resistances at coupling points vary greatly with the contact force and the surface condition.

1. General information about the welding circuit
2. Electrical resistance in the welding circuit

The resistance of a current-carrying cable depends on the cross-section, material, and length.
A high resistance causes a voltage drop and thus a power loss in the welding circuit.

Adequate dimensioning of the cable cross-sections can counteract this.

Recommended minimum cable cross-sections for uncooled copper cables and 100% duty cycle:

IMPORTANT! Position and fix components isolated to earth potential to avoid parallel resistances and current flows.

1. General information about the welding circuit

Every current-carrying conductor generates a magnetic field. If the amperage changes, the changing magnetic field induces a voltage. The voltage counteracts the change in current.
The inductance corresponds to the resistance to a change in current.

If the effective area between two conductors increases, the area of the magnetic flux increases and so does the inductance.

Individual inductances in the welding circuit, which add up to a total inductance

The inductance L [µH] increases due to the surrounding materials with their permeability µ_r and squares with the number of turns N of a conductor.

With the included area A and the materials µ_r, the inductance can be approximated using the formula for the ring-shaped air coil µ₀:

1. General information about the welding circuit
2. Inductance in the welding circuit

Every current-carrying conductor generates a magnetic field. If the amperage changes, the changing magnetic field induces a voltage. The voltage counteracts the change in current.
The inductance corresponds to the resistance to a change in current.

If the effective area between two conductors increases, the area of the magnetic flux increases and so does the inductance.

Individual inductances in the welding circuit, which add up to a total inductance

The inductance L [µH] increases due to the surrounding materials with their permeability µ_r and squares with the number of turns N of a conductor.

With the included area A and the materials µ_r, the inductance can be approximated using the formula for the ring-shaped air coil µ₀:

1. General information about the welding circuit
2. Inductance in the welding circuit

When welding with high inductances, rapid current changes can no longer take place at the desired rate of change because the maximum voltage of a power source (= U_Limit) is insufficient.
This is particularly noticeable with pulsed arcs and long hosepacks with high inductances in the welding circuit.

Influence of inductance on the current profile of a pulsed arc

At high inductance, the current actual value I_act does not reach the target current flow I_set due to the limited socket voltage U_clamp.

High-speed video sequence: Influence of inductance on droplet detachment during pulsed-arc welding

Same settings for sequence A1 - A2 and B1 - B2.

1. General information about the welding circuit
2. Inductance in the welding circuit

The welding circuit resistance and the welding circuit inductance are determined via the power source in the course of the R/L alignment.

After positioning the contact tip and starting the R/L alignment, the voltage drop and inductance in the entire welding circuit are determined. The ohmic resistance and the inductance are used to correctly document the arc voltage display and for process control.

Start R/L alignment:

Screenshot from R/L alignment, TPS 320i - 600i

Different inductance area and welding circuit resistances according to position on longitudinal chassis

1. General information about the welding circuit
2. Inductance in the welding circuit

Standard values of welding circuit resistance R and inductance L for possible process interference:

Assumptions:

Spray arc
The spray arc is most insensitive to high currents due to its almost constant current flow.

Conventional dip transfer arc
The short-circuit behavior is event-oriented.

LSC (Low Spatter Control)
With its prediction-oriented dip transfer arc strategy, LSC is sensitive to high inductances.
The disruption of the inductive decay behavior is significantly improved with the aid of an electronic switch in the welding circuit (e.g., hardware, TPS 400i LSC ADV).

CMT
Due to the cyclic process adjustment with each forward and backward movement of the wire electrode, CMT is between LSC and LSC ADV.

Pulsed arc
Pulsed arc variants are the most sensitive because high pulsed currents require low resistances and low inductances.
Adjusted PMC multi-arc characteristics with reduced rates of change and reduced current levels can be used as a remedy.

1. General information about the welding circuit

If an electrical conductor is in a magnetic field, a resultant force acts on it.
This is known as the Lorentz force and it depends on the current direction, magnetic field direction, and their orientation to each other.

Even the smallest magnetic force effects generate a geometric deflection of the arc.
This undesirable interaction is referred to as "magnetic arc blow".

MIG/MAG weldability depending on magnetic flux density:

• Use multiple tacking points
• Shorten the distance between the contact tip and workpiece
• Increase welding current (= increase arc pressure)
• Use run-off plates
• Demagnetization (see also from page (→))

Magnetized components can deflect an arc and interfere with droplet detachment.
The current-carrying wire electrode and the arc plasma also generate concentric magnetic fields, which are distorted at component ends and uneven air gaps and also exert a deflecting force on an arc.
Current-carrying parts of a clamping device retain a residual magnetism (= remanence) if they are made of a ferritic material. Aluminum, copper, and austenitic steels do not retain remanence.

Force effect on the arc due to magnetic fields:

I = Welding current [A]
B = Magnetic flux [mT]
F = Deflection force [N]

F = Deflection force [N]

The strength of the magnetic field in the component depends on the current level, the magnetic conductivity (material), the cross-section, and the number and size of the air gaps in the magnetic circuit.
Welding over the premagnetized current path can have a negative effect on stability.

Arc blow away from the ground connection:

The position of the earthing clamp is crucial for the current flow direction and its magnetic field in the component.
The electric current always chooses the shortest distance, with the same materials and cross-sections, and determines the arc deflection direction opposite to the earthing clamp.

1. General information about the welding circuit
2. Magnetic interference of the arc

If an electrical conductor is in a magnetic field, a resultant force acts on it.
This is known as the Lorentz force and it depends on the current direction, magnetic field direction, and their orientation to each other.

Even the smallest magnetic force effects generate a geometric deflection of the arc.
This undesirable interaction is referred to as "magnetic arc blow".

MIG/MAG weldability depending on magnetic flux density:

• Use multiple tacking points
• Shorten the distance between the contact tip and workpiece
• Increase welding current (= increase arc pressure)
• Use run-off plates
• Demagnetization (see also from page (→))

Magnetized components can deflect an arc and interfere with droplet detachment.
The current-carrying wire electrode and the arc plasma also generate concentric magnetic fields, which are distorted at component ends and uneven air gaps and also exert a deflecting force on an arc.
Current-carrying parts of a clamping device retain a residual magnetism (= remanence) if they are made of a ferritic material. Aluminum, copper, and austenitic steels do not retain remanence.

Force effect on the arc due to magnetic fields:

I = Welding current [A]
B = Magnetic flux [mT]
F = Deflection force [N]

F = Deflection force [N]

The strength of the magnetic field in the component depends on the current level, the magnetic conductivity (material), the cross-section, and the number and size of the air gaps in the magnetic circuit.
Welding over the premagnetized current path can have a negative effect on stability.

Arc blow away from the ground connection:

The position of the earthing clamp is crucial for the current flow direction and its magnetic field in the component.
The electric current always chooses the shortest distance, with the same materials and cross-sections, and determines the arc deflection direction opposite to the earthing clamp.

1. General information about the welding circuit
2. Magnetic interference of the arc

Two adjacent arcs with the same current direction attract each other.
The smaller the angle and the shorter the distance between the wire electrodes, the greater the mutual attraction.

Arc blow during TWIN welding

An arc in the pulsed phase exerts a strong magnetic field on the second arc.
Welding away from ground is advantageous because both arcs are forced forward.

1. General information about the welding circuit
2. Magnetic interference of the arc

Demagnetizing components reduces the arc blow and is achieved by means of cyclic remagnetization. Lifting magnets or demagnetizing devices can be used for cyclic remagnetization.
Applications include in pipeline construction or for components with production- or transport-related residual magnetism.

Simple alternative if the lifting magnet has no demagnetizing function:
Use of a TIG AC power source (e.g., iWave AC/DC) + short-circuited grounding cables on the wrapped component while reducing the current amplitude.

Demagnetizing with iWave AC/DC:

Demagnetizing with AC alternating field

Parameterization and measures for a decaying current curve:

1. Current offset = +10
2. AC half-wave waveform:
   Positive half-wave = sine
   Negative half-wave = sine
3. Main parameters:
   DownSlope > 10.0 s
   Final current = 3 A (= minimum)
   Main current = approx. 300 A
4. Wrap welding power-lead around the component at least 3 times
5. Press torch trigger in 2-step mode

1. General information about the welding circuit

If several arcs are being used to weld one component or in one welding cell, the routing of the hosepacks and grounding cables is a decisive factor in their mutual interference.

The following figure shows two parallel grounding cables.
The red cable (a) has current flowing through it and induces a voltage in the gray cable (b).
The magnitude of the induced voltage is described by the coupling factor (M).

Decaying coupling factor due to distance

The coupling factor is inversely proportional to the distance (d). The greater the distance, the lower the induced voltage.

A minimum distance of 30 cm is recommended.

1. General information about the welding circuit
2. Interference coupling

If several arcs are being used to weld one component or in one welding cell, the routing of the hosepacks and grounding cables is a decisive factor in their mutual interference.

The following figure shows two parallel grounding cables.
The red cable (a) has current flowing through it and induces a voltage in the gray cable (b).
The magnitude of the induced voltage is described by the coupling factor (M).

Decaying coupling factor due to distance

The coupling factor is inversely proportional to the distance (d). The greater the distance, the lower the induced voltage.

A minimum distance of 30 cm is recommended.

1. General information about the welding circuit
2. Interference coupling

Disruption of voltage flow U₂ due to induced voltages of a second circuit

The figure shows the idealized current waveforms (I) in red and the idealized voltage waveforms (U) in blue of two power sources.
Power source 1 induces a coupling voltage (U_c) into the welding circuit of power source 2 during welding.

This coupling voltage adds to or subtracts from the arc voltage and distorts the actual ratios of arc length and droplet detachment and their measured values for the second power source.
As a result of this interference, a cyclic change in arc length occurs.

The figure also shows a typical setup with parallel hosepacks and return lead cables, which couple mutually induced voltages. Separating the welding circuits or having a sufficient distance between the current-carrying conductors does away with this magnetic coupling (see also page (→)).

Uneven seam progression with interference voltage coupling into the welding circuit:

Arc length interference due to induced voltages of a second circuit
Series A: Welding result with coupled arc length interference
Series B: Welding result taking into account remedial measures

The arc changes that lead to this undesirable welding result are visible in the high-speed image and also to the naked eye.

Remedial measures as described in the optimization examples starting on page (→) reduce the arc length disruption.
A good welding result with a stable arc length is achieved.

1. General information about the welding circuit
2. Interference coupling

• The ohmic part shows the resistance value of a common grounding cable
• The percentage corresponds to the inductive coupling

Start welding circuit coupling:

IMPORTANT! The work steps must be performed on both power sources!

Result of the coupling measurement in mOhm (R_coupling) and % (k_coupling)

0 mOhm / 0%
Two completely separate welding circuits

High mOhm value
A great deal of static coupling, e.g., through shared grounding cables

High % value
A great deal of dynamic coupling, e.g., due to closely positioned, parallel hosepacks or return lead cables of external power sources
If two return lead cables or hosepacks are routed or wound together in one ferritic rail, this increases the mutual interference and thus the dynamic coupling.

The evaluation of the measurement results is divided into four ranges. If the measurement results fall within the lower two ranges, the welding circuits on one component should be optimized.

1. General information about the welding circuit
2. Interference coupling

If several arcs are being used to weld one component, the coupling values of the individual welding circuits in relation to each other should be determined. The individual coupling values add up when all arcs magnetically influence each other.

Recording the individual current paths and measuring, analyzing, and modifying them in pairs simplifies optimization of the welding circuits.

Adding the coupled magnetic interference using the example of 4 arcs on one component

How to perform a coupling measurement:

To achieve reproducible welding results, the electric welding circuit must be planned and optimized if necessary.
In addition to the position and length of the return lead cables, their attachment is also crucial to achieving welding results of consistent quality.

1. Structure of the welding circuit

To achieve reproducible welding results, the electric welding circuit must be planned and optimized if necessary.
In addition to the position and length of the return lead cables, their attachment is also crucial to achieving welding results of consistent quality.

1. Structure of the welding circuit
2. Grounding point design

To achieve reproducible welding results, the electric welding circuit must be planned and optimized if necessary.
In addition to the position and length of the return lead cables, their attachment is also crucial to achieving welding results of consistent quality.

1. Structure of the welding circuit
2. Grounding point design

A high contact force or surface pressure is required to ensure low contact resistances:

• Avoid ground connections spread over a large area
• Provide one or more point-shaped current application points

Screw terminals have the highest contact forces (> 1000 N).

Frequently used clamping elements and toggle clamps are usually not precisely defined, especially with regard to tolerances.

Grounding points – rigid variants

The figure shows point-shaped grounding point variants.
The pneumatic version with two grounding points has additional spring-loaded clamping cylinders for different forces and diameters.

Grounding points – rail systems

The second figure shows sliding grounding contact variants, used on or in rail systems.
A high surface pressure is also of great importance for these systems. Therefore, it must be ensured that the sliding block cannot lift off.
In many cases, a circuit is designed with two spring-loaded sliding blocks to stop this happening.
Dirt deflectors or wiper systems keep the rail free of dust and insulating grease.

1. Structure of the welding circuit
2. Grounding point design

Each welding circuit requires its own grounding point or grounding rail, which must be sufficiently dimensioned.

IMPORTANT!

• A clean surface is a prerequisite.
• Clean oxidized grounding contacts.

1. Structure of the welding circuit
2. Grounding point design

There are variants with sliding grounding contacts for rotating devices and components:

Grounding points – rotating components

Important features of grounding contacts for rotating devices:

• Sufficient contact force
• A separate grounding contact for each welding circuit
• Grounding greases with copper or graphite fillers are not recommended!
  (Can be used as an alternative if sufficient contact force cannot be achieved)

1. Structure of the welding circuit
2. Grounding point design

Planning multiple grounding points can significantly reduce the length of the current paths and inductance areas. Shared grounding cables are avoided and current paths are separated.
To obtain approximately equal resistance values, return lead cables should be of equal length and run parallel to the welding positive hosepack for as long as possible.

Grounding points – net-shaped routing on the hall floor

The figure shows the grounding cables routed in a net shape on the hall floor.
Large longitudinal chassis would have very high resistances and inductances with long drag chains for the hosepack and return lead cable.

• The power source is mobile and positioned on the boom (a).
• The carriage of the boom travels on rails (b) in the hall
  
  Aim:
  To weld the longitudinal seams of the beam (f).
  
• The sliding grounding contact (e) on the grounding rail (c) always guarantees a welding circuit (d) with a small area and low resistances and inductances.

1. Structure of the welding circuit

In the case of compact welding systems with an integrated wire drive and without an interconnecting hosepack, short torch hosepacks are usually also used.
Here, the routing of the return lead cable in particular must be taken into account:

• Keep the return lead cable as short as possible
• Lay the return lead cable without coils

This results in:

• Low inductances < 10 μH
• Low resistances < 15 mOhm
• No interfering influencing factors – all desired process current changes can be realized

1. Structure of the welding circuit
2. Notes on welding circuits in manual welding systems

In the case of compact welding systems with an integrated wire drive and without an interconnecting hosepack, short torch hosepacks are usually also used.
Here, the routing of the return lead cable in particular must be taken into account:

• Keep the return lead cable as short as possible
• Lay the return lead cable without coils

This results in:

• Low inductances < 10 μH
• Low resistances < 15 mOhm
• No interfering influencing factors – all desired process current changes can be realized

1. Structure of the welding circuit
2. Notes on welding circuits in manual welding systems

In split welding systems, a separate wirefeeder is connected to the power source via an interconnecting hosepack.
The length of the interconnecting hosepack and its arrangement are decisive factors in the inductance in the welding circuit.

Winding the interconnecting hosepack on the trolley or, in the worst case, around the gas cylinder multiplies the total inductance in the welding circuit.

Remedy
Wind return lead cables and interconnecting hosepacks in opposite directions:

Opposite winding of interconnecting hosepacks and grounding cables

The figure shows how the interconnecting hosepack is picked up in the middle and then wound up.

Compensated interconnecting hosepacks

With compensated interconnecting hosepacks, the welding positive lead and return lead cable are routed in one hosepack.

Compensated interconnecting hosepack with both polarities in one hosepack, between power source and wirefeeder

Almost the entire magnetic field is compensated for by means of an internal "4-strand arrangement".

In shipbuilding and pipeline construction in particular, this special solution can be a variant for short return lead cables and low inductances.

1. Structure of the welding circuit

Especially in automated systems or robot applications, the welding circuit must be planned first in order to exclude or reduce process interference in advance.
Subsequent planning and also optimization can often only be implemented at great expense.

The system design should use the same return lead cable lengths and cross-sections for the different grounding points.
The effective area between the hosepack and the grounding cable determines the inductance and should be kept as small as possible.

Component or device should be isolated from ground potential to avoid parallel ground currents and voltage potential shifts.

1. Structure of the welding circuit
2. Notes on welding circuits in automated welding systems

Especially in automated systems or robot applications, the welding circuit must be planned first in order to exclude or reduce process interference in advance.
Subsequent planning and also optimization can often only be implemented at great expense.

The system design should use the same return lead cable lengths and cross-sections for the different grounding points.
The effective area between the hosepack and the grounding cable determines the inductance and should be kept as small as possible.

Component or device should be isolated from ground potential to avoid parallel ground currents and voltage potential shifts.

1. Structure of the welding circuit
2. Notes on welding circuits in automated welding systems

Systems with one grounding point

Example – rotating unit with longitudinal chassis

• One grounding point at the end of the component
• Very long current path
• Large area between welding positive and ground results in undesirably large inductance
• Welding is carried out towards ground, which results in magnetization of the component

Longitudinal chassis with one grounding point

Remedy:
Setup with multiple grounding points

Longitudinal chassis with two grounding points

The second figure shows the longitudinal chassis with an additional grounding contact.
The areas between the welding positive lead and the return lead cable across the component become significantly smaller and also more constant over the travel path.

1. Structure of the welding circuit
2. Notes on welding circuits in automated welding systems

• When changing the current path, the different force effect on an arc may require the "away from ground" welding direction in the application.
  
• For components with an air gap, provide both halves with a grounding point to avoid magnetic flux across the welding gap.
  
• Run the welding positive lead and grounding cable in parallel for as long as possible to achieve mutual compensation.
  
• Use equal return lead cable lengths and arrange them in an optimized way.
  
• Maintain a sufficient distance from the machine bed or ferritic materials.

1. Structure of the welding circuit

Both manual and automated processes can use multiple arcs on a single component, which can lead to magnetic coupling effects.

1. Structure of the welding circuit
2. Welding with multiple arcs on one component

Both manual and automated processes can use multiple arcs on a single component, which can lead to magnetic coupling effects.

1. Structure of the welding circuit
2. Welding with multiple arcs on one component

If several arcs are being used to weld one component simultaneously, all welding circuits must be separated from each other:

• Avoid shared grounding points
• Avoid return lead cables and hosepacks routed in parallel
• Route current paths of different machines separately
• Do not run current paths under another arc

Possible errors in the cable layout and how to optimize them

Result of optimization:

• Small inductance areas (f) in contrast to large areas (c)
• Coupling values (A): 15 mOhm / 60%
  Coupling values (B): 0 mOhm / 0%

1. Structure of the welding circuit
2. Welding with multiple arcs on one component

Interference voltages from neighboring welding circuits influence the arc length control and lead to instabilities in the welding process (see also from page (→)).

Remedy:
Direct voltage measurement by means of sensor cable (c) from component to the next system bus interface (e.g., wirefeeder (b), SplitBox, or SB 60i)

From this interface, the voltage potential is transmitted to the power source without interference.

Sensor cable from component to wirefeeder

The figure shows the circuit diagram of the sensor interfaces (a) and (b).
The sensor cable is routed separately from the SpeedNet bus communication (e) but in the same multipole robot cable in the hosepack.

The physical effects of resistance and inductance due to the welding circuit arrangement do not change, since these are determined by the current-carrying cables (hosepack and return lead cable).
The measurement of the arc voltage is improved, and interferences in the voltage measurement are eliminated.

IMPORTANT!
Improving the hosepack arrangement is always the first optimization choice.

The distance (d) from the sensor cable to the return lead cable or hosepack should be at least 30 cm, if possible, to avoid coupled voltages in the sensor cable.

Single-wire welding systems usually do not require a sensor cable.

1. Structure of the welding circuit
2. Welding with multiple arcs on one component

If several arcs are being used to weld one component, the sensor cable brings a significant improvement in the voltage measurement and thus the arc stability, if the hosepack and ground wiring has not been optimally designed.

Example: Rotary table with the welding area behind a partition wall

Sensor cable from component to wirefeeder for improved voltage measurement, when hosepack and ground wiring are not designed optimally

• Two robots weld simultaneously on one component, (e) = partition wall
• Unfavorable arrangement of return lead cables (-) 1 / (-) 2 and hosepacks (+) 1 / (+) 2
• The welding circuit of power source 1 couples an induced voltage into the welding circuit of power source 2 – correct measurement of the arc voltage is not possible.
• One sensor cable (c) per welding circuit at a sufficient distance (d) from the current-carrying cables transmits the arc voltage to the wirefeeder without interference, and from there, shielded to the power source.

Multiple welding positions require multiple grounding contacts and sensor cables on the device. These must also be arranged with sufficient spacing to avoid coupling.

Several sensor cables can be routed together in one cable harness, since they do not carry welding current and do not cause mutual coupling.

With long welding gantries, a sensor cable does not bring any advantages. Therefore, short welding circuit lengths should be planned when designing the system.

The following optimization examples are described in the next sections:

• Several individual welding systems on one component
  
• TWIN welding system
  TWIN welding systems are multi-wire welding systems that are isolated from each other and have at least two consumable electrodes in a shared weld pool.
  
• Multiple TWIN welding systems on one component
  Two or more TWIN systems on one component multiply the risk of mutual interference.

1. Optimization examples

The following optimization examples are described in the next sections:

• Several individual welding systems on one component
  
• TWIN welding system
  TWIN welding systems are multi-wire welding systems that are isolated from each other and have at least two consumable electrodes in a shared weld pool.
  
• Multiple TWIN welding systems on one component
  Two or more TWIN systems on one component multiply the risk of mutual interference.

1. Optimization examples
2. Optimization examples

The following optimization examples are described in the next sections:

• Several individual welding systems on one component
  
• TWIN welding system
  TWIN welding systems are multi-wire welding systems that are isolated from each other and have at least two consumable electrodes in a shared weld pool.
  
• Multiple TWIN welding systems on one component
  Two or more TWIN systems on one component multiply the risk of mutual interference.

1. Optimization examples
2. Optimization examples

Multiple individual welding systems on one component – before optimization

• Parallel grounds and parallel hosepacks reciprocally couple interference into the welding circuits.
• Shared ground nodes or grounding rails mean 100% coupling of one circuit into the other.
• The figure shows transposed return lead cables in the upper sketch, resulting in crossing current paths in the component.
• When using a ground node, the current path changes from power source 2 via grounding point 1 (shown in the figure in the lower sketch) due to the shorter path or lower resistance.

1. Optimization examples
2. Optimization examples

Multiple individual welding systems on one component – after optimization

• Two separated welding circuits that do not affect each other and have no shared grounding points.
• The danger of current paths crossing in the workpiece in a known working area is avoided after circuit planning.
• The inductance areas are significantly reduced, which makes it easier to regulate the target current ramps and thus ensures stable weld droplet detachment.

The images from before and after optimization are shown in an enlarged view underneath.

1. Optimization examples
2. Optimization examples

TWIN setup before optimization

• Both power sources stand together on a podium.
• Return lead cables as well as robot hose packs are arranged in parallel.
• Both return lead cables are arranged in a shared steel tray.
• Hosepacks positioned close to one another on the robot.
• Large effective inductance areas.

1. Optimization examples
2. Optimization examples

TWIN setup after optimization

• Both circuits are separated from each other.
• In the TWIN welding circuits, the welding positive lead and return lead cables are each routed as parallel as possible to keep the inductance areas low.
• The hosepacks are separated and routed in drag chains with the greatest possible distance between them.
• Both return lead cables are routed in separate channels and ideally fastened or clamped directly to the component.
  ==>
  Two recommended variants:
  a) For components with a gap, divide the return lead cables between both halves (lower sketch).
  b) Arrange the earthing clamps so that welding is carried out away from ground (upper sketch).

The images from before and after optimization are shown in an enlarged view underneath.

1. Optimization examples
2. Optimization examples

Multi-TWIN system before optimization

• The concentration of all power sources in one place results in an unfavorable routing of hosepacks and grounding cables together.
• The parallel arrangement of the hosepacks without sufficient spacing or running them all along steel girders and trays together increase the mutual interference.

1. Optimization examples
2. Optimization examples

Multi-TWIN system after optimization

• Separation of the TWIN welding systems with their own welding circuits.
• Long parallel routing of the hosepack and the associated return lead cable – the inductive effective area is reduced and at the same time the magnetic field in this section is compensated.
• As soon as the TWIN hosepack splits into two individual hosepacks at the Y-junction, lay the two individual hosepacks as far apart from one another as possible (min. 30 cm).
• Two separate drag chains or sufficient spacing (min. 30 cm).

The images from before and after optimization are shown in an enlarged view underneath.