700021 — Alarm 700021 (Lubricant level too low) Diagnostic Tree

This alarm code (700021) is not found in the uploaded standard Siemens source manuals. The 70xxxx series alarms in the NC/PLC interface are typically machine builder (OEM) specific PLC alarms (the 'Lubricant level too low' message usually indicates a warning from the level float or sensor in the lubrication tank). Please check the guideway/spindle lubricant tank and refill with the correct oil if necessary, verify the sensor is functioning, or consult the machine manufacturer's documentation / technical support.