Introduction For any machinist, setup technician, or maintenance engineer running a Mori Seiki (now DMG MORI) CNC lathe or machining center, few things are as jarring as a sudden halt in production accompanied by a cryptic EX alarm on the control panel. Unlike standard CNC machine alarms (which often relate to servo overloads or program errors), EX alarms are machine manufacturer-specific. They are the machine tool builder’s way of telling you about a hardware limit, a missing input signal, or a safety violation.
This article serves as a complete reference guide. We will break down what EX alarms are, how to access them, the most common alarm numbers by machine series (NLX, NH, DuraTurn, etc.), their probable causes, and step-by-step solutions. Definition An EX (External) alarm is a user-defined or builder-defined alarm that originates from the PLC (Programmable Logic Controller) inside the machine. While the CNC control (Fanuc, Mitsubishi, or Siemens) handles axis movement and spindle speed, the PLC handles the "body" of the machine: coolant pumps, chip conveyors, door locks, hydraulic units, tool changers, and safety interlocks. mori seiki ex alarm list
Never bypass an EX safety alarm (e.g., door interlock or chuck clamp confirmation) to save cycle time. They exist to protect both the operator and the multi-ton machine investment. When in doubt, call a certified DMG MORI service technician – but now, with this guide, you’ll know exactly which EX alarm to report. Need the exact EX alarm list for your specific model? Leave a comment with your machine’s year and control type, and we can narrow down the most common failure points. This article serves as a complete reference guide