Hardware reference guide

Modbus Plus NOMs
35013379 02 October 2007 283
LED Indicators
and Descriptions
The following figure shows the Modbus Plus NOM LED indicators.
The following table shows the Modbus Plus NOM LED Descriptions.
LED Descriptions
LEDs Color Indication when On
Ready Green The module has passed power-up diagnostics.
Run Green Indicates that the unit is in kernel mode–should always be OFF
during normal operations.
Modbus Green Indicates communication is active on the single RS-232 serial port.
Modbus+ Green Indicates communication is active on the Modbus Plus port.
Error A Red There is an error condition on Cable A of a dual cable Modbus Plus
network (140NOM21200 only).
Error B Red There is an error condition on Cable B of a dual cable Modbus Plus
network (140NOM21200 only).
Ready
Error B
Modbus +
Error A
Run
Modbus
This document provided by Barr-Thorp Electric Co., Inc. 800-473-9123 www.barr-thorp.com