Siemens 840D Alarm 380000 — What It Means
Alarm 380000 on the Siemens Sinumerik 840D indicates a drive enable signal is missing — the safety logic that allows the drives to energize hasn’t received its enable signal. On the 840D, the NCU (Numerical Control Unit) communicates drive enable status through the DRIVE-CLiQ or X121/X122 interface; if the enable chain is broken, no axis or spindle drive can be powered.
Common Causes
- E-stop circuit not reset — The most common cause. The emergency stop circuit is still active, preventing drive enable from being asserted.
- Safety relay or contactor not closed — The machine’s safety relay chain (door interlocks, light curtains, safety mats) has an open element that prevents the drive enable signal.
- DRIVE-CLiQ enable signal fault — The enable signal transmitted over DRIVE-CLiQ from the NCU to the drive modules is not being received correctly.
- Commissioning parameter not set — On a newly configured or restored machine, a parameter controlling drive enable may not be correctly set.
Step-by-Step Fix {#fix}
- Reset the E-stop — Twist and release all E-stop buttons on the machine and operator panel. The E-stop chain must be fully clear before drive enable can be asserted.
- Check door and safety interlocks — Verify all machine doors are fully closed and all safety devices (light curtains, safety mats) are in their normal/cleared state.
- Check the safety relay module — In the control cabinet, locate the safety relay or PLCopen safety module and verify its status LEDs indicate the safety circuit is closed.
- Cycle the axis enable switch — On the 840D operator panel, use the axis release key switch and press the drive reset/enable button sequence per the machine documentation.
- Check DRIVE-CLiQ connections — If the above steps don’t clear 380000, inspect DRIVE-CLiQ cable connections between the NCU and first drive module.
Parts Often Needed
| Part | Notes |
|---|---|
| Safety relay module | Amazon | Replace if safety chain won’t close |
| DRIVE-CLiQ cable | Amazon | Replace if enable signal transmission is interrupted |
| E-stop button | Amazon | Replace if button is stuck in depressed state |
When to Call a Pro
840D safety circuit and drive commissioning issues require Siemens-trained service. Do not bypass safety interlocks to clear Alarm 380000.
Related Articles
- Siemens Sinumerik 828D Alarm Codes Guide — Complete Diagnostic Reference
- Siemens Circuit Breaker Fault Codes - Complete Guide
- Siemens Desigo BMS Fault Codes - Complete Guide
- Siemens Cerberus/MXL Fire Alarm Fault Codes — Troubleshooting Guide
- Siemens G120C VFD Fault Code Guide — Complete Diagnostic Reference