low battery LED is ON a GE fanuc. PLC controller? What to do?
If the “Low Battery” LED is ON on a GE Fanuc PLC controller, it indicates that the backup battery’s voltage is low and needs to be replaced. Here’s what you should do:
- Identify the Battery Type: Check the PLC model and refer to the user manual to identify the correct replacement battery type. GE Fanuc PLCs often use lithium batteries, but the specific type may vary by model.
- Order a Replacement Battery: Obtain the exact replacement battery from a reliable source. Ensure the new battery is compatible with your PLC model.
- Backup the PLC Program and Data: Before replacing the battery, it’s crucial to back up the PLC program and any stored data to avoid data loss during the replacement process. Use the programming software or a backup device.
- Replace the Battery:
- Make sure the PLC is powered ON while replacing the battery. This ensures that the RAM contents (program and data) are not lost.
- Open the battery compartment following the manufacturer’s instructions. Usually, the battery is located on the CPU module.
- Carefully remove the old battery and replace it with the new one, ensuring proper polarity.
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Dispose of the Old Battery Properly: Follow local regulations for the safe disposal of the old battery, as it may contain hazardous materials.
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Verify and Clear the Alarm: After replacing the battery, the “Low Battery” LED should turn OFF. If it does not, check the battery installation and ensure the replacement battery is fully charged. Some PLCs may require a reset or acknowledgment to clear the alarm.
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Regular Maintenance: Schedule regular checks or replacements to prevent unexpected battery failures in the future. If the “Low Battery” LED remains ON even after replacing the battery on a GE Fanuc PLC controller, follow these additional troubleshooting steps:
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Ensure Proper Battery Installation:
- Double-check that the new battery is installed correctly, with the right polarity and securely connected. A loose or improperly connected battery could prevent the PLC from recognizing the new battery.
- Verify Battery Voltage:
- Use a multimeter to measure the voltage of the new battery to ensure it is not defective. A new battery should have the correct voltage specified in the PLC manual (typically around 3V for a lithium battery).
- Check for Residual Alarms:
- Some GE Fanuc PLCs might require a reset or an acknowledgment to clear the “Low Battery” alarm after the battery replacement. Refer to the PLC manual to see if there is a specific procedure to clear alarms.
- Inspect the Battery Contacts and Connections:
- Ensure that the battery contacts inside the battery compartment are clean and not corroded. Dirty or corroded contacts can prevent proper battery function. Clean them if necessary.
- Check the PLC Program Settings:
- In some cases, the PLC program settings might need to be adjusted or reloaded. Ensure that the PLC is correctly configured to recognize the new battery status.
- Restart the PLC:
- Power cycle the PLC controller by turning it OFF and then back ON. This might reset the internal status and clear the “Low Battery” LED if it’s a minor software glitch.
- Check for Firmware or Hardware Issues:
- If the “Low Battery” LED is still ON after all the above steps, there could be a deeper hardware or firmware issue. Consider contacting GE Fanuc support or checking if there is a firmware update or a specific known issue related to the model you are using.
- Replace the CPU Module (if necessary):
- In rare cases, a persistent “Low Battery” light can indicate a malfunctioning CPU module. If the issue remains unresolved after all checks, the CPU module may need to be repaired or replaced.
By following these steps, you should be able to troubleshoot why the “Low Battery” LED remains ON after replacing the battery in your GE Fanuc PLC controller.