If the equipment has been dry for eight or ten years or even longer, then the capacitors on the DC bus are what you have to suspect. This is one of the most common situations we encounter when repairing Siemens drives. The DC bus capacitors are responsible for energy storage and filtering to keep the voltage flat and stable. As the years go by, the capacity of the capacitors slowly goes down. A lot of equipment when no load running happily, a spindle or servo axis began to open the spindle, accelerate, F30003 suddenly appeared.
The reason is very simple: the capacitor is old, can not store so much electricity. The characteristics of this fault is particularly obvious: no load is fine, an acceleration on the report, a large load on the report, and the alarm frequency is getting higher and higher. If you have the equipment on hand just on these articles, we strongly recommend that you check the status of the DC bus capacitor.
It's true that things can go wrong inside the driver, but don't be so quick to condemn it to death!
Of course, not all F30003s rely on the outside. Some drives have been in use for many years, and the internal electronics have deteriorated, which can also throw you this alarm. For example, rectifier bridge damage, voltage detection circuit abnormalities, power module failure, circuit board aging or power sampling circuit does not work. These problems are usually not visible to the naked eye, the external power supply is clearly normal, the alarm is not wrong.
If you have confirmed that the input voltage is normal, three-phase is not missing, wiring is secure, capacitance is not a big problem, but F30003 or back and forth out of that only need to drive the internal hardware to investigate.
The machine has already given you a message, but you do not care!
Many devices have signs before F30003 pops up. For example, the machine suddenly stopped by itself, the servo axis is enabled to report an error, dry work occasional reset, the load is added to the system reboot, the drive panel flashes undervoltage prompts, or sometimes this alarm is with other power alarms a piece of the emergence of the class. If these symptoms appear in piles, in all likelihood, it is the power supply chain which link is not reliable.
How to find out what's wrong when you're in the field
When we fix a machine in the field, we don't usually rush to remove the drive. We have stepped on many pits over the years and know that the highest efficiency is found in the external power supply. The first measure of three-phase input voltage is normal or not. Then check circuit breakers, fuses, contactors, terminal blocks, many problems can be uncovered in this step. If there is no problem with the external power supply, then use STARTER or SINAMICS comes with diagnostic tools to catch the DC bus voltage trend curve. Especially look at the moment the motor starts, if the voltage slashes down a knife, you can go along to check the capacitor, rectifier part or power module. It's much faster than swapping modules blindly with your eyes closed.
Always take the reset button hard to carry, sooner or later carry out a big trouble!
Some factories deal with the F30003 by pressing the reset button and running the machine. Temporarily, it seems to be able to deal with the past, but over time the hidden danger will be big. Long-term undervoltage will make the IGBT work in an abnormal state, the current becomes larger, the capacitor life shrinks faster, the power module is also very hot. Small problems dragged dragged into the real drive damage, to that time the repair cost can be several times the current.
The extra care you take can save you a lot of money in downtime!
From a maintenance point of view, the F30003 alarm is actually better prevented. Regularly check the quality of the power supply, take a screwdriver to tighten the terminal rows one by one during maintenance, look at the contactor contacts burned or not, pay attention to the operating temperature of the drive, for the age of the equipment to the initiative to assess the remaining life of the capacitor. These things are not insignificant, but can help you avoid a lot of unexpected downtime. Especially in continuous production plants, the loss of one stop is often enough for you to do do dozens of preventive maintenance.
