I/O Expansion; General Description - Motorola ACE3600 RTU Owner's Manual

I/O EXPANSION

General Description

The ACE3600 RTU includes the option of expanding the number of I/O modules controlled by
a single CPU module on the main frame. The I/O expansion frames can be co-located with
RTU on the main frame (installed in the same 19" rack or cabinet) or distributed in the same
site (up to 50 meters from the main frame.)
I/O expansion is based on a 100 Base-T full duplex Ethernet connection between the CPU
module and the expansion modules. This type of connection enables the user program
application to control and monitor the I/O modules on the expansion frames transparently in
the same way it controls and monitors the I/O modules on the main frame.
The user can diagnose all the modules on the expansion frames using the STS via the CPU on
the main frame. The STS can also be connected locally through the expansion module's STS1
RS232 port.
I/O expansion is based on three modules:

Expansion LAN Switch: This module is part of the expansion frame. It is installed in
the main frame in an I/O module slot. Up to seven expansion frames can be connected
through a single expansion LAN switch. (For one expansion frame, the switch is not
required.) Eight to thirteen expansion frames can be connected using a combination of
two expansion LAN switches. For information, see the Expansion LAN Switch
chapter below.

Expansion Power Supply: This module is installed in the I/O expansion frame. It
extends power (and 12V DO control) from the power supply on the RTU's main frame
to the I/O expansion frame, or from one I/O expansion frame to another. For more
information, see the Expansion Power Supply Module chapter below. This module can
be replaced by another ACE3600 power supply option per power requirements or
when the expansion frame is not co-located with the main frame. For a list of power
supply options, see the Power Supply Module and Backup Battery chapter above.

Expansion Module: This module is part of the expansion frame. It is installed in the
I/O expansion frame next to the power supply. It is connected via LAN to the RTU's
main frame, either to the CPU module or to the expansion LAN switch, depending on
the configuration. For more information, see the Expansion Module Chapter below.
Note: Only a dedicated LAN should be used by the main CPU and expansion modules to
communicate with each other. Connecting other elements to the LAN may disrupt system
operation.
Note: The main CPU must include an Eth1 Ethernet port. Therefore, only the CPU 3640
can be used for I/O expansion.
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