04 high frequency introduction, 05 high frequency interference, 06 electromagnetic compatibility – Tweco 175 TE Arcmaster User Manual

Page 25: High frequency introduction -3, High frequency interference -3, Electromagnetic compatibility -3, Installation arcmaster 175 te

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instaLLation

arcmaster 175 te

Manual 0-5116

3-3 Installation

3.04 High Frequency Introduction

The importance of correct installation of high frequency

welding equipment cannot be overemphasized.

Interference due to high frequency initiated or

stabilized arc is almost invariably traced to improper

installation. The following information is intended

as a guide for personnel installing high frequency

welding machines.

!

WARNING:

EXPLOSIVE The high frequency section

of this machine has an output similar to

a radio transmitter. The machine should

NOT be used in the vicinity of blasting

operations due to the danger of premature

firing.

!

WARNING:

COMPUTERS It is also possible that

operation close to computer installations

may cause computer malfunction.

3.05 High Frequency Interference

Interference may be transmitted by a high frequency

initiated or stabilized arc welding machine in the

following ways:
1. Direct Radiation: Radiation from the machine

can occur if the case is metal and is not properly

grounded. It can occur through apertures such

as open access panels. The shielding of the high

frequency unit in the Power Source will prevent

direct radiation if the equipment is properly

grounded.

2. Transmission via the Supply Lead: Without

adequate shielding and filtering, high frequency

energy may be fed to the wiring within the

installation (mains) by direct coupling. The

energy is then transmitted by both radiation and

conduction. Adequate shielding and filtering is

provided in the Power Source.

3. Radiation from Welding Leads: Radiated

interference from welding leads, although

pronounced in the vicinity of the leads, diminishes

rapidly with distance. Keeping leads as short as

possible will minimize this type of interference.

Looping and suspending of leads should be

avoided where possible.

4. Re-radiation from Unearthed Metallic Objects:

A major factor contributing to interference is re-

radiation from unearthed metallic objects close

to the welding leads. Effective grounding of such

objects will prevent re-radiation in most cases.

3.06 Electromagnetic Compatibility

!

WARNING

Extra precautions for Electromagnetic

Compatibility may be required when

this Welding Power Source is used in a

domestic situation.

A. Installation and Use - Users Responsibility
The user is responsible for installing and using the

welding equipment according to the manufacturer’s

instructions. If electromagnetic disturbances are

detected then it shall be the responsibility of the user

of the welding equipment to resolve the situation

with the technical assistance of the manufacturer. In

some cases this remedial action may be as simple as

earthing the welding circuit, see NOTE below. In other

cases it could involve constructing an electromagnetic

screen enclosing the Welding Power Source and the

work, complete with associated input filters. In all

cases, electromagnetic disturbances shall be reduced

to the point where they are no longer trouble-some.

NOTE

For 230 VAC operation, have a qualified

person install according to applicable

codes, and instructions.

NOTE

The welding circuit may or may not be

earthed for safety reasons. Changing the

earthing arrangements should only be

authorized by a person who is competent

to assess whether the changes will

increase the risk of injury, e.g. by allowing

parallel welding current return paths which

may damage the earth circuits of other

equipment. Further guidance is given

in IEC 974-13 Arc Welding Equipment -

Installation and use (under preparation).

B. Assessment of Area
Before installing welding equipment, the user shall

make an assessment of potential electromagnetic

problems in the surrounding area. The following shall

be taken into account.

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