Chapter Four
Configuration
man_905_2.0.doc
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Chapter Four
CONFIGURATION
4.1
Introduction
The 905 modules may be configured by connecting a computer (PC) using the 905 Configuration
Software programme. Alternatively, the module may be configured by the on-board miniature
switches located under the blue cover on the front of the module. This chapter describes the default
configuration of the module and using the Configuration Software Programme. For details on switch
configuration, please refer to the separate 905 Switch Configuration Manual, available from 905
distributors.
Each 905 module is configured with a system address and a unit address. The system address is
common to every module in the same system, and is used to prevent "cross-talk" between modules
in different systems. Separate networks with different system addresses may operate independently
in the same area without affecting each other. The system address may be any number between 1
and 32 767. The actual value of the system address is not important, provided all modules in the
same system have the same system address value.
A system address of zero should not be
used.
Each unit must have a unique unit address within the one system. A valid unit address is 1 to 127.
A network may have up to 95 individual modules communicating via radio (unit addresses 1 to 95),
each with up to 31 modules communicating via RS485 (unit addresses 96 to 127). In the network,
any individual input signal may be "mapped" to one or more outputs anywhere in the system. The
unit address determines the method of communication to a module. Any module with a unit address
between 96 and 127 will communicate by RS485 only. Other units with a unit address below 95
may communicate by radio
or
RS485 - the unit will determine which way to communicate
depending upon the unit address of the destination module. For example, Unit 31 will talk to Unit
97 by RS485 only, but will talk to unit 59 by radio only. 105S units must always have a unit
address between 96 and 127 as serial communication is the only method of communication
available.
A unit address of zero should not be used.
The three different products in the range can be used together in the same system. Inputs to one
product type can be transmitted to outputs of another product type. For example, an analogue
input to a 905-2 may be transmitted to an analogue output of a 905-1 or 905-3. Repeaters may be
any product type.
The 905-1 and 905-2 modules require only one unit address. The 905-3 module uses two
addresses, however only one unit address has to be entered. The 905-3 module requires two
addresses because of the large number of output channels. If the “entered" unit address is an even
number, then the second address is the next number. If the "entered" address is an odd number,
then the second address is the previous number. So the two addresses are two subsequent
numbers, starting with an even number. If a 905-3 module is given a unit address of 10, then it will
also take up the unit address 11 and will accept messages addressed to either 10 or 11. It is
important to remember this when allocating unit addresses to other modules in the system.