Any way to factory reset a Micrologix 1100?

I have a Micrologix 1100 that I've been working on, and now it is showing a blinking fault light. On the LCD screen, it say Major Fault 0008h. I had connected to the PLC through RSLogix just prior to testing the program and receiving the fault code, but now I can't connect to it. There is a red X over the PLC's IP address and says it can't be located.

The only way I know to clear the fault is through RsLogix, so I'm kind of stuck now. Is there any other way to clear the fault? Or to reset the PLC's memory so the faulty program is no longer loaded?

Assuming that this fault can be recovered:

You should be able to set the IP address by using the keypad and LCD display or by using BootP. Then power cycle it once it is set as static and BootP is turned off. Make sure (using the keypad) that the IP address is intact and then you should be able to download the project.

I believe that error will cause the Micrologix to dump its program so you will be forced to perform a download. Make sure the PLC is well grounded.

We had a customer with a similar problem recently. The cause apparently was a loss of power. Their unit was on a UPS and the voltage may have dropped out and come back up. It seems like the 1100 doesn't like brownouts as well as it likes blackouts. I have seen this a couple of times with the 1100. I have not seen it with the 1400.

More info that may not apply to your situation: In our case, as a preventive measure, I enabled the system bit to clear errors and return to run mode on power up. In our case there was also a "retentive memory lost" error. Our case, however, the PLC retained the channel settings which was handy since there was no backup of the program and it was using the finicky radio modem protocol. I did have to invent a program out of thin air for it but at least I did not have to research what the channels settings needed to be.

Have you tried to connect to the serial port?

Pull the battery out while it is powered off and wait a while.

It's true that 1100 always have this problem. AB should recall this product.

BachPhi said:

It's true that 1100 always have this problem. AB should recall this product.

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People should also design better power supply circuits. I use DC UPSs for exactly this reason. Why stress your expensive PLC to save $200 bucks on power supplies?

Saffa said:

People should also design better power supply circuits. I use DC UPSs for exactly this reason. Why stress your expensive PLC to save $200 bucks on power supplies?

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Fair point but most if not all ML1100s require 120VAC power. And having UPSs are a double edged-sword. It can require a separate isolation to perform a proper LOTO. Most people are used to just opening a single disconnect on a panel, not having to throw a separate switch/breaker in addition.

I bought a MicroLogix 1100 16BWA for use in training and of course the red light fault was flashing on initial start up to test the integrity of the PLC. I used the following to clear the fault:
PLC model: Micrologix 1100
Symptom: FAULT red light blinking
Solution:
Press ESC,
Press down to Mode Switch
Then press OK
Press Up to Program
Then press OK
Press down to Run
Then press OK
This cleared the initial blinking light and left two green lights

June 6, 2018
Regards,
Johnne in Seattle

Note the battery just powers the clock. I unplugged mine for days and it retained the program.