Ptu Network Connections; Ptu Network Software Commands; Unit Network Id - FLIR PTU-D300 User Manual

PTU-D300 User's Manual (v2.19)

7.2 PTU Network Connections

Figure 6 illustrates how PTUs can be networked and connected to a host computer via its RS-
232 port. Each PTU has a built-in RS-232 to RS-485 converter, and the host computer can be
connected to the RS-485 controller network by simply connecting to the RS-232 connector on a
PTU. The PTUs are then connected together via an RS-485 multi-drop network (full duplex).
120 1% terminator
HOST
COMPUTER
Figure 6: Making PTU Network Connections
Several issues are important to note when you make your own data cables. First, use a good
quality cable. Though a good quality telephone cord cable can be used, use of a twisted pair cable
is highly recommended. A twisted pair whose impedance is about 100 is typically used for
longer RS-485 runs. The twisted pair provides good noise immunity owing to the relative signals
used by the RS-485 standard.
For some applications, the host computer may directly provide RS-485 full-duplex I/O. In
this case, you may directly connect your host computer to the PTU network. For computers with
only RS-232, RS-485 connections may be simply made using an external RS-232 to RS-485
converter. FLIR Commercial Systems, Inc. has tested/qualified two converters: ATEN IC-485S
and Moxa A50 which both require a flipped RJ-12 connector (such as a standard phone cord). It is
important to note that the network should be terminated using 120 1% resistors to protect
against signal ringing on the network. Termination is achieved by placing the resistors between
the RS-485 Transmit+/Transmit- and Receive+/Receive- wires at each end of the multidrop
wiring network.

7.3 PTU Network Software Commands

This section describes the pan-tilt command set used to configure, set and query the network
configuration of your PTU controllers.

7.3.1 Unit Network ID

Description
Specify or query the PTU controller network unit ID number. By default, the
PTU unit ID is set to zero which indicates the PTU controller is not
networked, and the PTU controller is in the default interactive
communications mode. When assigning a unit ID number to a controller, the
unit ID number should be unique, the controller should be the only PTU
controller attached to the host computer or terminal (otherwise other
RS-485 Multi-Drop Network
• • •
net/termin. network
PTU-NCONN
(full duplex)
• • •
net/termin. network
PTU-NCONN
NETWORKING
120 1% terminator
network net/termin.
PTU-NCONN
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