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Rockwell Automation 1772-L8_LW_LWP_LX_LXP,D17726.5.8 User Manual User Manual

Page 106

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Maintaining and Troubleshooting

Your Processor

Chapter 6

6-3

Table 6.F

The PROC Indicating LED Will Help You Troubleshoot Your Processor

If the PROC indicator

And the processor

You should

Green

is in the Run mode operating normally

program is executing

outputs are enabled.

is in MEM STORE mode and EEPROM memory module is

being programmed. The indicator will be ON for a few seconds

and then then turn OFF.

No action required

Blinking Green

has an I/O configuration error

there is an illegal backplane switch combination (i.e., switch

4 is ON, switch 5 is OFF)

the I/O is not in complementary fashion (32Ćpt. I/O only).

Check the switch settings and

module placement.

Red

has a possible hardware failure

program is not executing

if switch 1 of the switch group assembly if OFF, outputs are

disabled

data lines on the I/O chassis could be shorted to ground

Cycle power.

If the problem still persists, call your

AĆB representative.

Off

is operating normally in Program or Remote Test mode
is operating in Run mode, it has a memory or program error

Change the processor to Program mode, correct

problem and cycle power.

If problem still persists, call your

AĆB representative.

Watchdog Timer

The watchdog timer monitors the operation of the processor hardware. If
something goes wrong with the hardware (electronic circuit failure within
the processor), the watchdog timer times out after 250 milliseconds and a
processor fault (red PROC indicator light) occurs. You then must recycle
power to clear the fault. If repeated faults occur, return your processor
for repair.

Processor Faults and Run-Time Errors

For information on run-time errors, see chapter 26.

Processor Removal

If the Processor is the suspected source of a fault, replace it.

Fuses

A fuse in the processor has no visual indicator. When a fuse is blown, the
processor appears dead (since there is no power) and no indicators
are lighted.