Motorola Piccolo-XR Owner's Manual page 9

Introduction
PIU - Piccolo Interface Unit
The Piccolo Interface Unit (PIU; see Figure 2) is connected to
the IRRInet Field Unit (FU) via RS232
or RS485 serial ports.
Each PIU supports up to 256 Piccolo–XR units, with any
available I/O combination, limited by the capacity of the
IRRInet software only.
Utilizing the S&F technology and networking capabilities, the
PIU can be linked to Piccolo–XR units positioned in distances
of up to 1500-2000 meters (approx. 1 mile), depending on
topography, antenna type and antenna installation.
The PIU is an interface between the Piccolo–XR and the
IRRInet FU, which provides communication and networking
operations only. (Monitor and control features are not included
in the PIU.) That is: The control and monitor functions are
provided either locally, by the Piccolo–XR or by an upper
hierarchy unit (i.e. IRRInet FU).
The PIU is a portable device, which is used in fixed
installations enclosed in an indoor plastic housing.
The PIU must be installed by qualified and authorized
technicians, so as to meet applicable safety standards and to
ensure protection against weather hazards for the unit.
If the PIU will be connected to outdoor lines, an interface unit,
complying with Clause 6 of the UL 60950 standard must be
provided.
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