Sinumerik 810 GA1 T shutting down problem

Hello!

I have a problem with Sinumerik 810 GA1 T.

Since 3 months CNC 810 GA1 sometimes shuts down by itself. 3 months ago it happened once a week, one month ago once a day, but now every 1 or 2 hours. I’ve already checked the external power supply. It seems good (20VDC < my 24VDC < 30VDC) – I checked it using an oscilloscope. I’ve even changed the external PS, but the problem persists (of course to eliminate fan problems I’ve enabled PS by a short-circuit jumper). Furthermore fan works.

The internal PS 6EV 3055-0BC in my opinion works fine. I’ve checked it on the desk without load (measured voltage: +5.13; +15; -14.88). Enable, fan control and PS OK signals work good. During 12 hours of verification and testing on the desk PS doesn’t shut down at all.

I’ve perceived interesting fact on machine – when the system shuts down, then the monitor and whole system go OFF for over a dozen seconds, but after them they go ON without NC-ON signal (it works like a PS reset signal).

Sometimes after itself shutting down, I had a problem with re-enabling the CNC. Perhaps once I had to reinstall all data (TEA1, TEA2, PCP and so on), to three times helped the Eye and NC-ON, but usually CNC after the problem works good and needs to move lathe’s axes to reference points.

Is there anyone, who had confronted with this problem and has an idea to resolve it?

Regards

Jck

MBA thanks for quick reply.

However, Sinumerik 810 GA1 doesn’t have two fans at the bottom of the rack. It has one at the top above the modules and, as I wrote, it works good. I also deactivated fan control signal by jumpering enable signal at the internal power supply, but problem persists.

I’m looking for any other ideas.

Regards

Jck

Hi

The picture shows a part of the neutral point external transformer connection.

It was very loose, which finally led to the above problem.

The most important information, after checking the external and internal power supply was the fact, that Sinumerik 810 GA1 was starting automatically again without NC-ON signal.

The second symptom, that I recently noticed, was flickering of fluorescent lights at manufacturing hall.

Finally it turned out, that Sinumerik GA1 was working well, but the problem still persisted until repairing the connection shown in the picture.

Regards

Jck