User's Manual

User Guide
WherePort III User Guide D948 Rev B
©2010 Zebra Enterprise Solutions. WherePort and all product names and numbers are Zebra Enterprise Solutions trademarks. All oth
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Figure 19 Dual Where Port
Figure 20 Coverage Pattern
A single (A), adjacent (B), and dual WherePort (C) field are
shown. The fields shown are for WherePorts at power level 8
and mounted at the same height as the WhereTag.
3.7 Interference
Steel objects and some devices can interfere with the WherePort field and change its
shape and range.
Some kinds of structures will affect the range of the WherePort. Mounting the
WherePort on the broad face of a steel I-beam reduces the coverage on the front and back
of the WherePort.
The field can also be extended or ducted by steel in windows, metal studs,
conduit, or duct work. This is most likely to occur when the WherePort is within one to
two feet of the steel and the tag is also close to the steel. This could lead to an unwanted
increase in the size of the field.
Magnetic interference can block communication between the WherePort and the
tag. The most common sources of magnetic interference are CRT monitors, electric
motors, vehicle RFID anti-theft ignition systems, and other WherePorts. A WherePort
may not ping a tag that is within one to two feet of an operational monitor or industrial
motor. The field strength meter can be used to check for interference.
A
B
C