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

Siemens S120 F30015 fault - diagnosis and fix

doug_forming

Siemens S120 F30015 fault on our servo press. Here's what we found and how we fixed it. Posting in case it helps someone else.

Common Causes:
- Actual phase loss: Check incoming L1/L2/L3 at the infeed module under load. A loose terminal at the cabinet entry is the most common culprit.
- Asymmetric loading: Regenerative braking during slide deceleration can create momentary voltage asymmetry. Check if the fault only occurs during deceleration.
- DC link voltage ripple: If the Active Line Module (ALM) is undersized, excessive ripple can trigger F30015. Check r0070 during a press cycle.
- Firmware mismatch: S120 firmware below 4.7 SP2 has a known false F30015 issue on high-inertia loads. Check p0018.

Diagnostic Steps:
1. Check r0949 (fault value): 1=L1 missing, 2=L2, 4=L3, 7=all three (usually firmware issue)
2. Monitor r0070 (DC link voltage) during a cycle
3. Verify p0210 (supply voltage) matches your actual supply
4. Verify ALM sizing: rated current should be at least 1.3x peak motor current

If the fault is intermittent at high SPM, the ALM is likely undersized. Adding a braking resistor as a buffer can resolve this without replacing the ALM.

mchen_servo

On F30015. Check parameter p0864 (infeed operation enable) on S120 with Active Line Module. If this drops to 0 during the press cycle due to a brief supply dip, it triggers F30015 even when phases are physically present. Seen this on high-SPM lines with 2-3 percent voltage sag during peak production hours.

anna_plc

F30015 on S120 can also be triggered by harmonic distortion on the incoming power. If you have VFDs or other non-linear loads on the same transformer, the voltage waveform gets distorted and the power module temperature calculation goes wrong. We added a line reactor on the S120 input and F30015 stopped appearing.

raj_pm

Adding a PM angle to this thread. We track F30015 on our S120 fleet (4 presses) and saw it cluster around shift starts in winter — points to thermal/condensation issues rather than pure firmware. Two things that cut our occurrence rate ~60% over 18 months:

1. Cabinet heater + dewpoint sensor on the drive bay. Anything below 8°C cabinet temp on cold mornings was correlated with first-cycle F30015 events. $180 in hardware, paid back inside a quarter on avoided callouts.

2. Quarterly clamp-on logging at the LCL filter terminals. We caught a degraded contactor on one press that was producing dirty switching transients only under load — easy 5kA spike fix that explained months of intermittent faults.

For documentation: we keep a one-page "F30015 first-response card" laminated in each cabinet — p0864 / p0840 check, DC bus voltage threshold, then escalate. Took the average MTTR on this fault from 35 min to 8 min for our shift techs. Happy to share the template if anyone wants it.