Kitamura Mycenter 3 keeps blowing fuses

[jh84]

Hello!

I recently bought Mycenter 3 -89 with Fanuc 11M controller.I got machine home, first tested it outside my shop. Got it running ,everything worked ,turned spindle and ran some programs with it. Then i moved machine indoors to its place. Did second test, machine ran OK otherwise but when i stopped running program or turning spindle, spindle started to turn counter clockwise slowly. (I dont know if this is related to problem i'm having now) Anyway re-started machine and it worked normal like first time i tested it.

Some days later i was about to move Y-axis to different place to get machine cleaned better. I turned main power on , turned control power on. 20 sec later i got alarm on display EX04 fuse open alarm. It blew F5 fuse (Daito P413, 1.3a). Replaced fuse, gave second try.Now it blew F6 fuse immediately when main power was on. Replaced F6 fuse (same Daito P413 as F5) gave another try. Now F5 and F6 fuse blew same time when main power was turned on.

I got Kitamura maintenance manual, but to be honest after couple of hours looking of it i'm not much wiser. Here is some photos of manual. If someone could point where to look for problem or narrow down the search.

I checked between phases, power was same 403v

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[Algirdas]

Did you check the phase sequence? If there is some ( hydraulic pump; coolant pump ) three phase motor without VFD, it should run to right direction.
Double check the voltages first of all. Your

I checked between phases, power was same 403v

looks great, just double and triple check again. It is easy and doesn't take a lot of time and it is most important at this condition.
Narrow the circle of suspects.
Disconnect the power supply from distribution terminals making the parts of equipment unpowered. Check which part makes the fuse blow.

[jh84]

UPDATE

Got machine running. There is electric cabinet fans (inblowing and outblowing on top) with wires marked with R4 and S4. So i unhooked fans, these two and one under power source. Machine ran normally. I ran it only 20min cause i didn't have fans working.

These two fans are changed at some point (made in germany). I measured ohms one had 62 ohms other had 132 ohms, are these around what it suppose to be? There was no obvious short circuit.

I noticed that there is one fan under spindle control unit that didn't run in those 20min i used machine. (could have something to do unhooking other fans?) Is it supposed to run all the time?

So i don't still know if the machine is fixed, or did i have some lucky coincidence. Because maintenance manual points these fuses to either coolant (COL1 relay, third picture i send on first post) or spindle control unit. (fourth picture on first post)

Any input or pointers are very welcome!