Wireless Pushbuttons
Battery-Free Wireless Pushbutton Modules for Building
Technologies and Industrial Automation
 When planning new industrial buildings and plants
intellegent automation solutions are more and more considered, often using
several decentralised control units. However, the wiring of the necessary
control elements is quite quickly becoming expensive and inflexible.
Wireless pushbuttons, which do not require any cable, are
the solution for this problem. They need no wiring at all and allow very
flexible handling and arrangement of the switches and pushbuttons.
Conventional wireless pushbuttons, however, do have two
disadvantages: They use batteries for the power supply, on the one hand,
which must be changed regularly. On the other hand, the signal
transmission takes relatively long (approx. 50 to 70 msec.), which may
result in an overlapping of two switching operations so that one of the
two signals gets lost.
One way out of this dilemma offers the innovative wireless
transmission technology from EnOcean. This technology provides the
required energy from the processing and ambient energy. This disposable
energy is generated as kinetic energy e.g. during switching operations or
vibrations, or even as thermal energy (e.g. by light irradiations or
temperature differences). This procedure allows to operate the control
units without cable connection and even without batteries, thus, making
the units wireless, self-powered and low-maintenance.
The new wireless transmitter modules use this technology
for the battery-free transmission of a pushbutton signal. In this case the
required energy is produced by the switching operation itself, thus,
making it independent from ambient conditions.
Transmission of the radio signal takes place on the
licence-free SRD band (Short Range Devices) at 868 MHz with a transmission
power of 10mW. Three very short telegrams are sent within 25 ms, including
an individual 32-bit ID, the polarity of the supply voltage and the actual
playload (one to two input signals). This multiple emitting guarantees
utmost transmission security.
The EnOcean wireless standard at a glance :
High Reliability
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Licence-free 868 MHz frequency band with 1% duty cycle
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Multiple telegram emitting with checksum
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Ultra-short telegrams (approx. 1ms) reduce collision risk
to a minimum
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Broad reach: 30m in buildings & 300m in a free field
-
Repeater available for range
extension
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Unidirectional and
bidirectional communication
Low Energy Requirement
Interoperability
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Wireless protocol defined
and integrated in modules
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Sensor profiles specified
and implemented by users
-
Unique transmission ID (32
bits)
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Coexistence with other
wireless sytems
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No interference with DECT,
WLAN, PMR systems etc.
-
System design verified in
industrial environment
The transmitted signals can be processed by all receiver
modules that recognise the EnOcean wireless standards, provided they have
been programmed for the specificity of our pushbuttons, which is already
implemented e.g. in the 4-channel relay modules and the radio receiver of
the WAGO-I/O system from WAGO Kontakttechnik GmbH & Co. KG.The
transmission range is up to 300 m in a free field but strongly depends on
the surrounding materials and the position of other energy generators or
metal surfaces. Hence, certain basic conditions have to be observed for
the installation planning, such as e.g. a min. distance of the receiver to
other transmitters or high-frequency sources of interference. A field
intensity meter allows to determine the optimal positions for sender and
receiver.The wireless pushbutton module from DUX and Schlegel is available
in two designs. The type DMF_A can be used as a contact element for all
2-position pushbuttons and 2-position selector or key switches. For the
3-position selector or key switches the model DMF_B is your choice. The
latter transmits two input signals whereas with the DMF-Y only one input
signal is sent.These modules have been designed to be combined with the
attractive actuators of the design awarded control unit series DUX-Basic.
The module DMF_A, however, can even be used for all suitable Schlegel
ranges. The module size is approx. 43 x 45 x 29 mm. The modules are
applicable at temperatures between - 25°C and + 65°C and are in accordance
with the R & TTE-EU Standards for radio equipment. We will be glad to send
you more details on request.
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