CTI 2500-RIO-B Installation and Operation Guide V1.4
9
Setting Remote Base Controller Station Address
A thumbwheel switch is provided to set the base address to the 2500-RIO-B for Remote I/O station
identification. A maximum of 15 remote bases can be connected to the CTI 2500 Series® CPU or
Siemens® 545/555/575 CPU.
NOTE:
When connecting the 2500-RIO-B to a CTI 2500 Series® CPU or Siemens® 545/555/575 CPU, only
addresses between 1 and 15 are valid. Each installed 2500-RIO-B must have a unique station
number.
Care should be taken to prevent circumstances which cause the CPU to lose communication with the
2500-RIO-B while the system is operating. Loss of communication between the CPU and RBC will
cause the base to be logged off from the CPU. This can cause intermittent process operation.
WARNING:
The following events will cause loss of communication with the 2500-RIO-B and result in the
base being logged off from the CPU.
1) Duplication of the station address between RBC’s attached to the same CPU
(except in dual-media applications).
2) Changing the thumbwheel switch station address while the system is operating.
These events could cause unpredictable process operation and result in damage to equipment
and/or serious injury to personnel.
When a base is logged off, the CPU zeroes all image register input points associated with the base
and all outputs go to the value determined by the installed output module. Discrete outputs turn OFF
(0) and Analog/Word outputs are set according to the Zero/Hold Last Value settings in each
particular module. Your program can monitor the CPU Status Words to detect this condition and
control the outputs from other remote bases as appropriate for the application. Details on the Status
Words and programming examples can be found in the SIMATIC®
545/555/575 Programming
Reference User Manual
.
Setting the Output State on Communication Loss
When I/O channel communication to a remote base is lost, the state of the discrete outputs is
determined by the selection made on the 2500-RIO-B jumper JP4 (Off/Freeze). Figure 2 shows the
location of the jumper on the 2500-RIO-B.
NOTE:
The 2500-RIO-B ships with the FREEZE jumper in the OFF setting.
If the jumper JP4 is missing from the board, the 2500-RIO-B defaults to the OFF setting.
For discrete output modules, the state of the outputs is determined solely by the position of the
Off/Freeze jumper JP4 on the 2500-RIO-B.
