OPTO 22 B3000-B, User Manual

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CHAPTER 4: MAINTENANCE AND TROUBLESHOOTING
B3000-B Serial Brains User’s Guide 21
Red and Green
If the STAT LED blinks red and green alternately, it indicates that the brain is in failsafe bootloader mode.
See “Resetting the Brain” on page 20 for more information.
Red
If the STAT LED blinks red , it indicates the following:
TROUBLESHOOTING A B3000-B OR B3000-B-OMUX BRAIN
Troubleshooting Checklist
If you are having trouble communicating with a B3000-B brain, check the following:
• Make sure the brain’s hold-down screw has been tightened so that it is snug. (Do not overtighten.)
• Make sure the brain has been turned on and that the STAT LED is lit (green). If the STAT LED is not green,
the brain may not be in normal mode. See below,
“Making Sure the Brain is in Normal Mode.”
• Make sure that power to the brain is sufficient. Each brain should have its own power supply. The brain
needs 5.00 to 5.20 VDC, measured downstream of the fuse on the rack.
• If you’re accessing the brain through a SNAP PAC S-series controller, make sure you can communicate
with the controller over Ethernet. For help, see the controller user’s guide (form 1592).
• Check physical connections between the controller or PC and the brain.
• Verify that the following serial parameters on the controller or PC and the brain correspond: baud rate,
address, 2-wire or 4-wire connections.
• Make sure termination switches are set correctly for all brains on the serial network.
Making Sure the Brain is in Normal Mode
If you are having trouble communicating with the brain, it might be in failsafe bootloader mode or hardware
test mode . The brain restarts in one of these modes if you hold down the RESET button longer than the time
needed to restore default settings. For more information on using the RESET button, see “Resetting the Brain”
on page 20 .
• Failsafe bootloader mode is used to update firmware. It is also used for troubleshooting a problem with
Opto 22 Product Support. You know the brain is in this mode if the STAT LED is blinking red and green
alternately. If your brain restarts in failsafe bootloader mode, simply cycle power to the device. This action
performs a simple restart and allows you to communicate with the brain.
Number of
Blinks
Speed of
Blinks
Means Problem and Workaround
4 slow
Incorrect serial settings. Invalid
hardware revision Check serial settings (See page 4 .)
Contact Product Support.
5 slow Fatal error
Firmware or hardware problem. Check the power
supply and connections before restarting. Call
Product Support if the error is repeated.
6 slow RAM error Contact Product Support.
16 slow Serial flash failure Contact Product Support.
20 slow Digital failure Contact Product Support.
21 slow Bus failure Contact Product Support.