QTech Data Systems Q26 Digital I__O Expansion Module User Manual
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DATRAN II eXcel –Q26 Quick Start Guide – v2.0 – September 2010
Module Address
As an IO expansion module that communicates with the master RTU (eXcel or QRTU) on
the RS485 bus, the module must have an address that is unique to that bus. The
expansion module is factory preset to address 3. Therefore if multiple expansion modules
are to be used on the same RS485 bus then their addresses must be configured. This is
achieved by setting a code on the block of 8 DIP switches located internally to the IO
expansion module casing.
The code for address is a binary code with switch 1 being the least significant bit. This
means that each switch has a numeric value associated with it, and the resultant address
is calculated when you add all the switch values that are in the “ON” state.
The module address can be any number between 1 and 239. The module address 0 is a
reserved address while module address 255 is used to re-load the factory default
configuration settings.
The value of each switch is as follows:
Module Address Switch Values
Switch Number
1
2
3
4
5
6
7
8
Value
1
2
4
8
16
32
64
128
For example, if a module needs an address of 22, the correct setting would be to have
switches 2, 3 and 5 on and the rest off. (2+4+16 = 22).
The back of the Q26 Users Guide has a full table of all valid addresses and their
corresponding DIP switch settings.
Status LED’s
ON :
This green LED is always on when the module is powered.
OK :
This green LED flashes on a 1 second cycle to show the CPU has not
locked
up. If it is on solidly or stays off, then the eXcel needs attention.
IP :
This yellow LED indicates that the module is currently sending comms
out its IPB port to communicate with the RTU.
ER :
This red LED is the Error Indication LED. The LED will flash a certain
number of times to indicate any error messages the module has been
configured to display from Q90.
Number of
Flashes
4
5
Message
IPB
Comms
Fail
Digital
Outputs
Fail