Technical Instructions
Modbus RTU Interface Module for SED2
Document Number 155-767
February 25, 2009
Page 4
Siemens Industry, Inc.
Hardware Setup,
Continued
LED Indicators
Figure 8.
There are a total of three bi-color LED indicators on the Interface Module. See
Figure 8. The NET LED displays communications activity on the Network (Modbus)
port.
•
The STAT LED displays the overall status of the Interface Module.
•
The LCL LED displays communications activity on the Local (SED2) port.
During normal operations, the NET and LCL LEDs will quickly alternate red and green
flashes, making it look almost amber; this is normal.
Table 1. Interface Module General Status LED (Stat).
For this state:
LED is:
To indicate:
No power
Off
No power applied to the device.
Run Mode
Flashing Green
(250 ms On, 250 ms Off)
Interface Module is operating
normally in RUN Mode.
Configuration Mode
Flashing Green
(1.5 sec on, 1.5 sec Off)
Interface Module is in
CONFIGURATION Mode.
Fatal Error
Flashing Yellow
(250 ms On, 250 ms Off)
Interface Module has
experienced a fatal error, and
has halted communication.
NOTE:
If the Interface Module has been installed correctly, the STAT LED will be
flashing green, and the LCL LED will be alternating so fast between red and
green that it will appear to be glowing amber.
Table 2. Network Communication Activity LED (NET).
For this state:
LED is:
To indicate:
Received Data
Red
Data from the Modbus Network.
Transmit Data
Green
Data onto the Modbus Network.
Table 3. SED2 Communications Activity LED (LCL).
For this state:
LED is:
To indicate:
Received Data
Red
Data from the SED2.
Transmit Data
Green
Data to the SED2.
