Brochure/Catalogue

Glossary

1-9

2-way isolation The input and output signals are separated electrically from each other and

decoupled. Potential differences caused by long wire lengths and common

reference points are eliminated.

3-way isolation Also decouples the power supply to the input and output circuit and enables

supply with only one operating voltage.

A/D converter Converts standardised analogue current and voltage signals into an 8-bit, 12-bit

or 16-bit digital signal. It may be necessary to convert analogue signals into

digital signals when you need the analogue signal from the surroundings to work

with the typical digital processing requirements of process monitoring.

AC Alternating current

Accuracy Describes the ability of an analogue signal isolating converter to transmit a

measured value as precisely as possible. It is specied in the percent deviation

from the measuring range end value at room temperature.

Active sensor In an active sensor, an electrical signal is generated from the measurement itself,

for example dynamometric or piezo-electric. Thus no auxiliary power source is

required. Because of their physical operating principals (since energy cannot be

sent during the static and quasi-static states), only a change in the measured

variable can be detected.

Actuator The actuator is a sensor counterpart – it converts electrical current into another

form of energy.

Alarm contact A switching contact that activates when a disturbance occurs (for example, an

overload or short circuit).

Ambient temperature DIN EN 60204-1 uses this term to refer to the temperature of the surrounding air

or medium at which the equipment can be properly and safely operated. This is

a part of the surrounding physical and operational conditions. Failure to maintain

this temperature level can invalidate the product warranty.

Analogue signal A signal is designated as an analogue signal if it transmits parameter information

that is innitely variable between a minimum and maximum value (this includes

instantaneous values such as current, voltage or temperature). This applies to

practically all real-world processes or states. It is theoretically possible to register

any small signal changes (there is a very large dynamic range).

Technical appendix/Glossary

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