[email protected] | Installation manual Omnicomm 2.0 terminals v2.2
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signal linearisation, compensation for additional factors, protection, galvanic isolation, etc., and therefore
may have di
ff
erent names.
Proximity impulse sensors with N-P-N output transistor and “open collector” output are typically used.
Sensors can have various operational principles, but the most common sensors are based on four principles:
• Capacitive: are triggered when brought into the zone of sensor sensitivity of the certain matter
(metal, plastic, glass, liquid, etc.). Their working range reaches up to 30 mm. Can be falsely
triggered by dust, dirt, rain, etc., and therefore are usually used in clean conditions and indoors.
• Induction: are triggered when brought into the metal zone. Available with up to 30 mm working
range. More protected from false positives, but do not work with non-metallic objects.
• With hall e
ff
ect or reed relay: are triggered when brought into magnet working range.
• Optical: are triggered by interruption of optical path. Some also work from re
fl
ected
fl
ux (in this
case, emitter and receiver are in the same casing) or from
fl
ux radiator (emitter and receiver are
made separately and may be positioned at a signi
fi
cant distance from each other).
Contact sensors (e.g. buttons, end switches, relays, max level sensors, maximum pressure sensors, bimetallic
temperature switches, etc.) or proximity sensors with N-P-N transistor may act as potential sensors. These
contact and proximity sensors commute power voltage or ground, and thus lead to changes in voltage at
the potential input of the Terminal. Analog sensors, described above, can also act as potential sensors.
