SKF IMx-16, User Manual

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INSTALLATION AND OPERATING INSTRUCTIONS
SKF Multilog On-line System IMx-8/IMx-8Plus
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SKF Multilog On-line System IMx-8/IMx-8Plus
User Manual
Revision E
If the IMx device is placed first or last in the bus chain, then an external bus
termination resistor must be connected to it. Note that there is no built-in termination
that can be activated by configuration.
An external resistor of 120 ohms is provided by SKF as well as double deck terminals
to facilitate its installation. This resistor is colour-coded black,
Figure 9 .
Figure 9 120-ohm resistor for RS485, bus termination
For more information regarding RS485 and Modbus, refer to "Modbus for SKF
Multilog On-line System IMx and SKF @ptitude Observer
” and also the application
note “General Modbus
Protocol Considerations for IMx
Devices”. Also, refer to the
tables and pictures in chapter 3.3 , for a complete list of connections and their location
on the device.
Note that the IMx does not provide fail-safe bias to the bus.
2.5.6 LED indicators
The IMx-8/IMx-8Plus have two LED indicators on their top end cap
–
so only visible
when any outer cabinet is opened
–
a green LED for Power and a red LED for
System, Figure 10 :
Figure 10 IMx LED Indicators
While the main software is reading the configuration and setting up the system, the
SYS LED is fast flashing at approximately four times per second. When the system
configuration is complete, the SYS LED will be off, if it remains solid on, this indicates
that the IMx is in an error state. In the latter case, contact TSG for advice and further
information.
Note that there is a thirty second delay after the configuration period before the
measurement results are provided, to ensure that the system is producing valid data.
The SYS LED also has a slow flash rate, at approximately once per second, the
functionality of which is software configurable. By default this is turned off, but for
example, it may be used to indicate sensor cable fault or cable fault from an external
communication source (e.g. Modbus). For configuration details refer to the @ptitude
Observer User Manual.