750 Serial spindle link error

The machine is a star sr32 with fanuc 16tt control. About 2 weeks ago, the machine began to give this alarm while it was booting up.

"750 Serial spindle link error" on HEAD 2.
later on after 10 seconds or so, it also gives the following -
401 X AXIS VREADY OFF -
401 Y AXIS VREADY OFF
401 Z AXIS VREADY OFF on head 1 and

401 X AXIS VREADY OFF
401 Z AXIS VREADY OFF on head 2.

I was simply turning off the machine, and power supply and turning them on again and alarm was going away easily.

But today, when i turn on the machine, the alarm condition became stable, whatever i did, i could not delete the alarm.

It also gives 19 on the led display of the spindle amplifier module.

I saw some advices the check optical cables? i do not know how and what to check..

Alarm Codes 19 and 20

The offset voltage of the phase U (alarm code 19) or phase V (alarm code
20) current detection circuit is excessively high. A check is made when the
power is turned on. If this alarm is issued, replace the SPM. If this alarm is issued
immediately after the SPM control printed circuit board is replaced, check the
plugging of the connectors between the power unit and SPM control printed
circuit board. ??

Anyone experienced before?

Try swapping spindle sensor, else try swapping cable, else might be the drive.

check contacts on external/main contactor too- had one that broke a spring on a starter contact, would boot intermittently due to sometimes single phasing if the contact didnt touch. dont rcall if it was alarm 19, but sounds familiar.

you can use most cellphone cameras to 'look' into the fiber optic cables- look at the end, one fiber should be bright purple, plug back in, look at other end, should also have one bright purple light...if both dark, look during reboot, some time-out/shut off... usually if the IREDs are going bad, one will be very dim- if you see a dim one, follow the cable back and look into the socket- if brighter, your cable is damaged. Iphones(at least one buddies at work) wont see infrared, but most others do- you can look at the end of your tv remote to test

I just fixed a high voltage spindle drive tonight on a 0-i, it was intermittrntly giving a serial link fault, and saying 'dc link fuse blown'. took the amp apart, there were two 100k ohm 2 watt resistors on the DC buss, one was noticeably dark- checked them and the 'new' looking one was wide open... replaced it and it came right up- this serial stuff has really been a thorn in my side lately...its great when it works, but stupid little things go wrong and it sends you on a wild goose chase...

Is this problem solved?

Quote:

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Originally Posted by tc429

check contacts on external/main contactor too- had one that broke a spring on a starter contact, would boot intermittently due to sometimes single phasing if the contact didnt touch. dont rcall if it was alarm 19, but sounds familiar.

you can use most cellphone cameras to 'look' into the fiber optic cables- look at the end, one fiber should be bright purple, plug back in, look at other end, should also have one bright purple light...if both dark, look during reboot, some time-out/shut off... usually if the IREDs are going bad, one will be very dim- if you see a dim one, follow the cable back and look into the socket- if brighter, your cable is damaged. Iphones(at least one buddies at work) wont see infrared, but most others do- you can look at the end of your tv remote to test

I just fixed a high voltage spindle drive tonight on a 0-i, it was intermittrntly giving a serial link fault, and saying 'dc link fuse blown'. took the amp apart, there were two 100k ohm 2 watt resistors on the DC buss, one was noticeably dark- checked them and the 'new' looking one was wide open... replaced it and it came right up- this serial stuff has really been a thorn in my side lately...its great when it works, but stupid little things go wrong and it sends you on a wild goose chase...

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Ah yes even if it's unlikely the problem you might as well check the three phase voltage as well as continuity about everywhere on your circuit up to the spindle motor as well as the DC link voltage. You should also unplug your motor and meg it just to be sure it's okay. Be careful with capacitor discharging so you do not get a deadly electrical shock from this.

Cheers.

Yeah, the problem is solved. This is not something related to wiring or so. It was a U phase current transducer failure on the drive power card - not the control one - We took off the drive and removed everything. We gave 24 volts of electric and saw that it was still blinking number 19 alarm on led screen. There was not any possibity of using even a small current, so we directly removed the current transducer from the board. Gave 24 volts again and the alarm had gone. I bought a brand new one - lucky me hard to find a new one - and it works just fine now.

In my case, the 2 resistors R51 and R52 on the DC buss were open. The resistors are on the main board of the Spindle Amplifier (not on the communications board).
Replace the 2 resistors at it might solve your problem. I've been searching for a solution all over the internet and couldn't find anything that worked, so now i decided that every time i solve a problem and fix something, i'll post it everywhere for anyone to see.