Orientation And Mounting Of Data Carriers - Balluff BIS U-4A7-082-01C-07-S4 Betriebsanleitung

BIS U-4A7-082- _1C-07-S4
Industrial RFID system - Read/write head
5
Application planning (continued)
Read/write range
When considering the data carrier, irrespective of
environmental influences and the read/write head used,
the achievable read/write range depends to a large extent
on the design of the data carrier antenna and the memory
chip used. In simple terms, it can be said that data carriers
that are particularly small mechanically or data carriers
mounted on metal tend to achieve a smaller range and
may not reach the value specified in the technical data. In
individual cases, the range of the selected data carrier
must be checked in the application.
For data carriers that meet the various requirements and
mounting brackets, see www.balluff.com.
5.6

Orientation and mounting of data carriers

For optimal operation of the identification system, it is
important to pay attention to the correct orientation and
mounting of the data carriers. Antenna polarization is an
important factor in this regard. The integrated antenna of
the BIS U-4A7 is polarized in a circular pattern, i.e. data
carriers can be positioned at any angle, but parallel to the
antenna surface. Alignment of the data carriers in the
longitudinal axis, along the main beam direction, results in
the data carrier becoming invisible to the read/write head.
Fig. 5-8: Alignment of data carriers
The circular antenna polarization is achieved by the
antenna radiating simultaneously in the horizontal and
vertical spatial axis. The circular antenna field is created by
superimposing the two spatial axes. For design reasons,
the radiation of the horizontal axis is somewhat stronger
than that of the vertical axis. When using data carriers with
linear polarization, a higher read/write distance can thus be
achieved if they are aligned horizontally to the read/write
head. Depending on the device variant, the axis difference
can be 20...50%.
The orientation of the BIS U-4A7 antenna can be
determined by looking at the flat side of the antenna cap
(see Fig. 5-9). If the flat side is facing up or down, this
corresponds to a vertical orientation. If the flat side is to the
right or left, this corresponds to a horizontal orientation.
www.balluff.com
BIS U-4A7 vertically oriented
(flat side up)
Weaker spatial axis
Data carrier vertically Data carrier horizontally oriented:
oriented: shorter range
Fig. 5-9: BIS U-4A7 horizontal/vertical antenna axes vs. data carrier
alignment
The optimal orientation of the BIS U-4A7 antenna depends
on the application and the orientation of the data carriers.
When using data carriers with antennas with circular
polarization, no alignment is required.
Stronger spatial
axis
longer range
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