GE 90-30 PLC Series Installation And Hardware Manual page 136

CPU374 Hardware Features
This module has eight LED indicators, an Ethernet Restart pushbutton, a standard CPU keyswitch,
three port connectors, and a shield ground connection tab (labeled "FRAME").
LED Indicators
There are four LED Indicators. Three relate to the Ethernet interface: EOK, LAN, and STAT.
These can be ON, OFF, FLASHING slow, or FLASHING fast in several different combinations.
The full functionality of these LEDs is detailed in GFK-1541, TCP/IP Ethernet Communications
for the Series 90 PLC User's Manual.
The fourth LED, PS PORT, is for the CPU's serial port and is not related to the Ethernet interface.
This LED will flash while data is being transferred through the SNP serial port connector on the
PLC power supply, and will stay off when the port is inactive. All Series 90-30 CPUs have this
standard serial port.
Ethernet Restart Pushbutton
This pushbutton performs four functions: LED test, Restart, Restart and enter Software Load state,
and Restart and enter Maintenance state. These are detailed in GFK-1541, TCP/IP Ethernet
Communications for the Series 90 PLC User's Manual.
GFK-0356Q Chapter 5 CPUs
PS
EOK
PORT
LAN
CPU 374
STAT
ON
OFF
ETHERNET
RESTART
STATION
MGR
PIN 1
LINK/ACT
PORT 1
100Mbps
LINK/ACT
PORT 2
100Mbps
FRAME
5
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