Option Adapters
870 USE 101 10 V.2 81
Front Panel Components, Continued
LED Indicators This Option Adapter has three LED indicat ors. Their functions are described in the table below.
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LED Status Function
MB+ ACT Green Indicates activity on one or both of the Modbus Plus ports (see
the flash pattern table below)
Off No activity on either Modbus Plus port
ERR A Red Indicates a communications failure on Modbus Plus port A*
Off No problems detected on Modbus Plus port A
ERR B Red Indicates a communications failure on Modbus Plus port B*
Off No problems detected on Modbus Plus port B
* If you are not using redundant cabling on the Modbus Plus link (i.e., if only one of the ports
is being used) the Error LED for the unused port will be on constantly when Modbus Plus
communication occurs on the network.