Press brake alarm codes: common categories and first checks
A CNC press brake alarm is the controller reporting a monitored condition out of range. The codes are controller-specific, but the categories are consistent. This page groups the common ones so you can narrow the fault.
A CNC press brake alarm is the controller telling you a monitored condition is out of range. The code itself is controller-specific, but the categories are remarkably consistent across Delem, Estun, Cybelec and other systems. This page groups the common ones so you can narrow the fault before you call. It is general guidance — the exact meaning and reset procedure for a code are always in your controller manual.
Axis and servo alarms
The most frequent category. An axis alarm means a servo axis (ram, backgauge X, R, or Z) did not reach its target, exceeded position error, or lost its reference. First checks: is the axis physically blocked by a part or tooling, are the limit switches and encoders clean and connected, and did the machine lose its home reference after a power cut. Re-home the axis and clear the alarm; if it returns, suspect the encoder, drive or mechanical binding.
Hydraulic and pressure alarms
A low-pressure or no-pressure alarm usually means low oil, a pump that is not building pressure, or a relief valve issue. Check the oil level and the pump sound first. A high-temperature alarm points to clogged cooling, low oil, or the machine working harder than its cooling can shed — shut down and let it cool rather than pushing through.
Backgauge faults
The backgauge is the axis most exposed to dust, offcuts and knocks. A backgauge alarm is commonly a blocked finger, a fouled linear guide, or a lost reference. Clear the debris, re-home, and check the guide is lubricated. Repeated backgauge drift is often a mechanical stop or a worn ball-screw, not an electronics fault.
Safety-input and E-stop alarms
These open the safety circuit: light curtain interrupted, door open, foot pedal or E-stop latched, or a guard switch not made. The machine will not cycle until the input is restored and the alarm cleared. Walk the safety loop, reset the E-stop, and confirm the curtain and guards are seated. Never bypass a safety input to make the machine run — that is how serious injuries happen.
What to record before you call
Note the exact code, when it appears (at power-on, mid-cycle, after a tool change), and what you already checked. A photo of the screen and the machine serial number lets us send the right fix the first time instead of a guessing exchange.
Questions we get asked
What does an axis or servo alarm mean?
It means a servo axis did not reach its target, exceeded position error, or lost its reference. Check for physical blockage by tooling or offcuts, clean and connected limit switches and encoders, and re-home after a power loss. If the alarm returns, suspect the encoder, drive or mechanical binding.
Why do I get a hydraulic low-pressure alarm?
Usually low oil, a pump not building pressure, or a relief valve problem. Check the oil level and the pump sound first. A high-temperature alarm points to poor cooling or low oil and should be cooled down before continuing.
My backgauge keeps faulting. What is wrong?
The backgauge is exposed to dust, offcuts and knocks. A fault is commonly a blocked finger, a fouled guide, or a lost reference. Clear debris, re-home, lubricate the guide. Repeated drift suggests a mechanical stop or worn ball-screw rather than electronics.
Is it safe to bypass the E-stop or light curtain to clear an alarm?
No. A safety-input alarm means the safety circuit is open for a reason, and bypassing it to make the machine run is exactly how serious injuries happen. Restore the input, reset the E-stop, and confirm the guarding is correctly seated.
Where do I find the exact meaning of my code?
In the manual for your specific controller model. This page groups the common categories to help you narrow the fault, but the precise code meaning and reset procedure are always in the controller documentation.
Stuck on a specific code?
Send us the exact code, when it appears, and a photo of the screen with your machine serial number, and we will route it to the engineer who knows your model.