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Electromagnetic Interferences (EMI)

Electromagnetic Interferences are generated by currents which

flow into the electronic circuitry of instrumentation. Some electro-

magnetic interferences originate in nature through atomospheric

phenomena, such as lightning and static electricity.

Electromagnetic Compatibility (EMC) Directives define two categories

(illustrated below).

Each category is further sub-divided into:

• Conducted EMI propagated by wires (such

as power or connection cables)

• Radiated EMI spread through the air

The effects of these electromagnetic interferences are the main

cause for:

• Incorrect equipment operation and therefore,

inaccurate measurements

• Damage to the equipment, itself

International Governing bodies have defined the EMI tolerance limits

for electronic instruments. The aim is to limit EMI effects and to reach

an Electromagnetic Compatibility (EMC) that permits all electronic

devices to operate normally, and in proximity with each other, without

having an adverse effect on their operation.

Electromagnetic Compatibility

Electromagnetic Compatibility of an instrument means that electro-

magnetic interferences will not compromise its functionality, and at

the same time, the meter itself will not generate interferences which

may affect other equipment. In Europe, the CE mark on a product

means compliance with the EMC Directives. The products must

meet the directives before they can be legally sold. The CE Directive

referring the the “Conducted and Radiated Emissions” is designated

as EN 50081-1, while EN 50082-1 defines the prerequisites for

“Susceptibility to the Conducted and Radiated EMI”.

The “Mission Statement” of Hanna’s Research and Development is

“a complete dedication in designing electroanalytical instruments to

monitor and safeguard the environment, in compliance with the CE

Directives”. The following provides a short list of the significance of CE

Norms and howwe comply with them.

CE Mark Definition and Compliance

All industries make use of electronic instrumentation for their daily operations. The increased use of electronic

equipment in many industries means that more instruments are used together and in conjunction with each other, often

in a very restricted area.

Proximity of equipment has increased the likelihood of interferences between various instruments, as well as the

instruments and the environment surrounding them. Improper operation of the equipment may result from these

undesired Electromagnetic Interferences (EMI).

Susceptibility

Directives which sets standards

for the amount of EMI a device

can withstand and still operate

normally and without incurring

any damage.

Emission Directives

Restrict the amplitude of the

signals emerging from a device.

• Radiated Susceptibility

Our instruments are not susceptible to

radiation generated by other equipment

that in turn can cause improper

operation, such as, automatic switching

off and/or inaccurate measurements.

• Radiated Emissions

The Hanna meters do not emit

radiation that might cause improper

functioning of other equipment in

their proximity (such as switching off

and/or inaccurate measurements).

• Susceptibility to Conducted Interferences

This is caused mainly by power leads

or signal/control cables connecting

different devices, which could result in

malfunctioning or permanent damage.

Hanna products come with this protection

• Electrostatic Discharges

Hanna equipment is not susceptible to

static electricity from users or objects,

whether due to direct contact or

proximity. This kind of discharge can cause

severe damage to other equipment.

Compliance with the CE Directives,

ensures reliability and accuracy for

products manufactured by Hanna.

Glossary

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