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A

Aluminium

Aluminium is a chemical element and belongs to the precious metals. It is a relatively soft metal. As it is very flexible, it can be processed easily by forging to thin film. Aluminum is a very good electrical conductor.

C

Carbon

Carbon is a chemical element. In nature it either appears chemically bound (such as hydrocarbon) or in pure form (such as diamond).

CE-mark

Many European directives specify that products must bear a CE mark. The manufacturer thus declares the product's compliance with all current European regulations and that it has undergone the specified conformity assessment process.
It should be noted that unlike the GS symbol, for example, the CE mark does NOT necessarily have to be awarded by an independent testing and certification body.

Compression set

The compression set is a measure of how elastomers behave in long-running pressure deformation and subsequent relaxation. The permanent deformation is an important parameter for seals of elastomer.
A compression set of 0% means that the body has fully achieved its original form, a compression set of 100% expresses that the body was completely deformed.

Copper

Copper is a chemical element. It is a relatively lightweight metal that is well workable. Copper is an excellent heat and power conductor.

Copper-beryllium

Copper-beryllium is a copper alloy containing 0.4 to 2% beryllium.
Copper-beryllium alloys provide very good mechanical and electrical properties. The strength they achieve after curing is the highest of all copper alloys and the curing process also achieves high electrical conductivity. Furthermore, CuBe is extraordinarily elastic.

Corrosion

Corrosion describes the reaction of a material with its environment wherein the material undergoes noticeable change. This change may adversely affect the function of the system or component.
Rusting is the most common type of corrosion. This is where metal oxidises

E

Elastomer

Elastomers are plastics, which elastically deform in tensile and pressure stress and then largely find back to their original form. However a deformation may occur at long lasting, constant pressure. Especially for the use of elastomerical materials the permanent deformation - the so-called compression set - is an important characteristic.

EMC

EMC stands for electromagnetic compatibility and is defined as follows in the European EMC Directive: The ability of equipment to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to other equipment in that environment.
In short technical equipment should not cause mutual disturbances for each other by means of undesirable electrical and electronic effects.

EMVG

EMVG is the Law concerning the Electromagnetic Compatibility of Equipment. It applies to all equipment which can cause electromagnetic disturbance or whose operation can be adversely affected by such disturbance and defines the appropriate EMC protection measures. The law refers to all electrical or electronic apparatus, systems and plants which contain electrical and electronic components.

EPDM

EPDM stands for ethylene propylene diene monomer and is an elastomer (rubber).

ESD

ESD is an abbreviation of electrostatic discharge (discharge of static electricity).
Electrostatic discharge is a spark which causes a very short, high current pulse.
It is primarily the electrostatic charging of human bodies which plays a leading role in electronics. The discharge from human bodies can damage or even result in the destruction of electronic parts, components and equipment.

Extrusion

In an extrusion process plastic or other highly viscous materials which harden (such as rubber, for example) is melted and then pressed through a shaping nozzle before being cooled. This produces components in a wide variety of shapes (depending on the cross-section of the nozzle) and arbitrary length. This process is used, for example, for the production of sections.

F

Ferrites

Ferrites are composed of a mixture of ferrous oxide, nickel, zinc or manganese oxides and have a crystalline structure. These materials are used for forming ferrite cores or ferrite beads. These feature high magnetic conductivity and are used, for example

  • in coils, throttles and transformers
  • in high frequency technology and for antenna production
  • to seal microwave devices
  • in power supplies and audio equipment, etc.

G

Graphite

Graphite is a frequently appearing mineral. It is one of the manifestations of the chemical element carbon in pure form. Graphite is hard and very well electrically conductive

GS-mark

The German GS mark (Tested Safety) confirms that a product meets the requirements of the Equipment and Product Safety Law. To enable a company to affix the GS mark to a product, the product must have been tested and certified by an approved test body.

H

Hardness

In general hardness means the mechanical resistance that a material opposes the mechanical penetration of a softer, equally tough or tougher body. The hardness is measured by the comparison of several materials or material conditions

HF radiation

High frequency electromagnetic waves are emitted for the wireless transfer of data in frequencies between 100 kHz and 300 GHz. This sees electrical and magnetic fields merge to form an electromagnetic wave.

High frequency radiation is used primarily by radio and television broadcasters, by radar, mobile phones and cordless phones, microwaves and baby monitors. The reason for this is the fact that their waves spread quickly and also the long range of HF radiation.

I

I/O shield

The I/O shield is also known as a connection cover or ATX cover. It is a piece of plate which is secured to the rear of a PC housing and integrates the I/O connections on the motherboard precisely into the housing.
The aims of the I/O shield are to minimise the dust that gets into the interior of the computer and to create an electromagnetic shield for the housing. An I/O shield is required if several USB devices are to be connected since otherwise interferences may occur

IP

Electrical and electronic components are often exposed to coarse ambient conditions (dirt, dust, moisture, etc.). The IP protection classes describe the extent to which a component may be exposed to these ambient conditions without suffering damage or posing a safety risk.

IP protection classes to DIN 40050 take the form IPxx. 
The first digit denotes the protection level against foreign bodies and contact whilst the second digit denotes the protection level against contact with water. 
The following is a list of the protection classes to VDE 0710 DIN 40050: 


First digit – protection level against the ingress of foreign bodies:

  • 0: No protection
  • 1: Protection against the ingress of solid foreign bodies with a diameter over 50 mm

  • 2: Protection against the ingress of solid foreign bodies with a diameter over 12.5 mm

  • 3: Protection against the ingress of solid foreign bodies with a diameter over 2.5 mm
  • 4: Protection against the ingress of solid foreign bodies with a diameter over 1 mm
  • 5: Limited protection against dust ingress
 6: Total protection against dust ingress

Second digit – protection level against water: 


  • 0: No protection

  • 1: Protected against vertically falling drops of water or condensation

  • 2: Protected against vertically falling drops of water if the housing is tilted at an angle of up to 15° 

  • 3: Protected against vertically falling drops of water if the housing is tilted at an angle of up to 60°

  • 4: Protected against water sprayed from all directions
  • 5: Protected against low pressure water jets from any direction
  • 6: Protected against high pressure water jets from any direction

  • 7: Protected against short periods of immersion in water
  • 8: Protected against long, durable periods of immersion in water. An additional digit denotes the immersion depth in metres.

 

ISO 14001

ISO 14001 was introduced in 1996 and is an environmental management system in which environmental protection is systematically set out in a management system. This means that environmental aspects are given due consideration in all company policy decision and day to day work.

ISO 9001

The introduction of a quality management system to a company is intended to provide the basis for systematic processes and quality which can be planned. The main aims of ISO 9001 are to improve the economy of a company using efficient processes, enhance practice and customer focus and to reduce risks in the development and introduction of IT systems.
In addition a certified company has an independent confirmation of quality which it can use to give it an edge over its competitors.

M

Monel

Monel is a nickel-copper alloy comprising approx. 65% Nickel, 33% copper and 2% iron. The high nickel content means that Monel has an excellent electromagnetic shielding effect. Furthermore it features high tensile strength and resistance to corrosion.
The name Monel is a trademark of Special Metals Corporation. Monel is regarded as a forerunner of stainless steel.

P

Polyester

Polyesters are versatile plastics which can be used to make a whole host of products, from textile fibres and PET drinks bottles to CDs and food packaging, etc.

Polyolefin

Polyolefins are the most important group of plastics. The main representatives from this group are polyethylene and polypropylene.

Polyurethan

Polyurethanes are synthetic resins or plastics. Depending on how they are produced, they may be soft and elastic or brittle and hard. The elastomers, in particular, are extremely tear-resistant.

R

REACH

Regulation (EC) No. 1907/2006 (REACH Regulation) of the European Parliament and Council came into force on 1 June 2007. This is a chemicals regulation on the registration, evaluation, authorisation and restriction of chemical substances. Chemical substances which are brought on to the market within the area covered by REACH must first be registered. The REACH Regulation is valid in all EU member states.

RoHS

EC Direction 2002/05/EC (RoHS Directive) came into force on 1 July 2006. It is applicable in all EU member states and restricts the use of certain hazardous substances in electrical and electronic equipment. To comply with the RoHS Directive these products must contain none of the following substances:

  • Mercury (Hg)
  • Lead (Pb)
  • Cadmium (Cd)
  • 6-valent chrome (Cr VI)
  • Polybrominated biphenyls (PBB)
  • Polybrominated diphenyl ethers (PBDE)
  • Decabromodiphenyl ethers (DecaBDE).

S

Shielding material

Users already have access to a large number of shielding materials. Starting with conventional spring contact strips made of copper-beryllium, plastics containing conductive carbon or other conductive particles, to plastics or elastomers which are simply covered with a wire mesh. The shielding effectiveness, compression force, mechanical and climatic conditions and, finally, their compatibility are all factors which must be given due consideration when selecting suitable products.

Shore durometer

Durometer is one of several measures of the hardness of a material. The durometer scale was defined by Albert F. Shore. Durometer is typically used as a measure of hardness in polymers, elastomers and rubbers.
Durometer measures the depth of an indentation in the material created by a given force on a standardized presser foot.

smd

surface-mounted device

The components are mounted or placed directly onto the surface of PCBs. An electronic device so made is called a surface-mount device (SMD). In the industry it has largely replaced the through-hole technology construction method of fitting components with wire leads into holes in the circuit board.

Stainless steel

Stainless steel is alloyed or non-alloyed steel with a particularly high level of purity.
Stainless steel contains at least 10.5% chrome. Stainless steel provides better corrosion resistance due to its having a passive layer which forms a barrier between the alloy and the surrounding materials. If this passive layer is damaged, it will repair itself automatically under the influence of oxygen.

U

UL 94

UL94 is a process designed to determine the various flammability classes of plastics. A distinction is made between the following classes:

HB: slow burning on a horizontal specimen V-2: a vertical specimen stops burning within 30 seconds V-1: like V-2 but drips of flaming plastic particles are not allowed V-0: like V-1, but burning stops within 10 seconds The UL symbol is issued by the American company Underwriters Laboratories®. A UL certification means that representative samples of the product have been tested and evaluated and have satisfied the requirements of UL. Further information is available at www.ul.com.