What is a servo press?

A servo press uses servo motors for precise force and position control during forming operations.

How do I calculate servo press tonnage?

Use our free tonnage calculator at servopress.club/tonnage-calculator.html

Fanuc Servo Alarm 414: Position Error Overflow — Fix Guide

admin

## What Is Alarm 414

Fanuc servo alarm 414 means the position error (difference between commanded and actual position) has exceeded the parameter setting. The press stops immediately.

## Parameter to Check

The position error limit is set in parameter 1828 (for each axis). Default is often 10,000 pulses. For a servo press with 1μm resolution encoder, 10,000 pulses = 10mm — this is too large for a press application.

Recommended setting: 500-2000 pulses (0.5-2mm) depending on press size.

## Common Causes

### 1. Acceleration Too High

If the press motion profile demands faster acceleration than the motor can deliver, position error builds up and triggers 414.

Fix: Reduce acceleration in the motion profile. Check parameter 1620 (acceleration time constant).

### 2. Load Inertia Mismatch

If the motor is undersized for the press inertia, it cannot follow the commanded position.

Check: Calculate inertia ratio. Should be below 10:1 for press applications. Above 30:1 will cause 414 alarms.

### 3. Mechanical Binding

Gib too tight, lubrication failure, or foreign object in the die area causes sudden load increase.

Check: Run press at 10% speed with no die. If 414 clears, the problem is mechanical load.

### 4. Servo Gain Too Low

If position loop gain (parameter 1825) is too low, the servo cannot correct position error fast enough.

Fix: Increase parameter 1825 by 10% increments until stable.

## Reset

Fix root cause first. Then: E-stop → release → RESET on operator panel.

anna_controls

On alarm 414, one diagnostic trick: temporarily double the position error limit and see if the alarm goes away. If it does, the motor is just barely exceeding the threshold and you may have a mechanical drag issue (tight gibs, low counterbalance) rather than a drive problem. If the alarm persists even with a wider limit, the encoder or drive has a real fault.

dave_toolmaker

One thing not mentioned: alarm 414 can also be caused by a failing encoder. If the encoder skips counts, the position error accumulates until it trips the alarm. Check the encoder signal quality with an oscilloscope before adjusting parameters. If the signal is noisy, replacing the encoder is the fix, not increasing the error limit.