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9.1.14 Read information of an ID tag
The information of an ID tag can be read via the objects 0x2180 to 0x2182. To do
so, the ID tag has to be within the detection range of the device.
The objects 0x2180 and 0x2182 are only valid as long as the ID tag is detected. If
there is no ID tag within the range, the values of the objects are reset to 0.
The value of the object 0x2182 can be read from the ID tag on request.
Reading of information is not supported by each ID tag type.
9.1.15 RSSI value
The RSSI value (Received Signal Strength, OD index 0x2162) informs about the
strength of the received signal that is emitted by the ID tag in front of the device:
“0“: no ID tag detected
“1“: minimum signal strength
“8“: maximum signal strength
The maximum signal strength is only reached with certain device / ID tag
combinations.
The signal strength depends on the distance between the ID tag and the
active face of the device.
Position changes in the environment, e.g. of metallic objects, can influence
the signal strength.
9.1.16 ID tag detection filter
The following situations result in undesired multiple ID tag detection and reading:
• The ID tag is in the limit range.
• The installation conditions have a negative effect on the electromagnetic field
of the device.
Thus, the ID tag is not clearly detected which leads to error messages while
reading or writing via PDOs. The objects "UID filter depth" and "Zero ID filter
depth" allow for error message filtering.