Allen-Bradley 1747-OC Series, User Manual

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1747-UM001A-US-P - March 2000
7-8 Using the Open Controller
During the power-on self test (POST), LED 1, LED 2, LED 3, and LED 4
indicate which test is running (if the STATUS LED is yellow) or which test
failed (if the STATUS LED is red). Table 7.D lists the LED patterns during
POST.
Table 7.D
LED patterns for LED 1, LED 2, LED 3, LED 4 during POST
This LED: Can have these states: Which indicate these tests:
LED 1 solid red
flashing red
solid green
flashing green
software CRC checksum
reserved
128K bytes RAM
dual-port RAM
LED 2 solid red
flashing red
solid green
flashing green
backplane
reserved
reserved
reserved
LED 3 solid red
solid green
reserved
temperature sensor
LED 4 solid red
solid green
interrupt controller
timer