Document Edition 3.4
Page 9 of 12
Indicators
LED
Function
Description
Power
Controller Power
Indicator
This yellow LED turns on to indicate that the controller has power
applied.
Scan
CPU Scan Indicator
This red LED flashes at a rate relative to the CPU scan rate.
Network
(Ethernet)
Ethernet
Communication
Status Indicators
The green LNK LED is turned on when a link is established
between two Ethernet devices. (for example, controller, computer,
switch, etc.) The green ACT LED flashes when communications
are active.
Network
(NET1)
MS/TP (RS485)
Communication
Status Indicators
The green LED flashes to indicate when the controller is
transmitting out the port, and the red LED flashes to indicate when
the controller is receiving data through the port. If communication
is good, both LEDs will flash at a high rate.
Network
(NET2)
MS/TP (RS485)
Communication
Status Indicators
The green LED flashes to indicate when the controller is
transmitting out the port, and the red LED flashes to indicate when
the controller is receiving data through the port. If communication
is good, both LEDs will flash at a high rate.
Inputs
(IP1
– IP16)
Input Status
Indicators
A corresponding red LED varies in intensity and is brightly lit when
the associated input is receiving a low voltage input signal (i.e. a
closed contact, 0 VDC, 0mA or a high temperature reading or low
resistance).
Outputs
(OP1
– OP16)
Output Status
Indicators
A tri-color LED is used. Under automatic control, the
corresponding output LED is green and is on or off to match the
status of an associated binary output. The LED will also vary in
intensity relative to the output signal for an analog output. With
HOA switches, the output LED is red in the OFF position and
yellow in the HAND position.
