[StefanL38]

Hello,

I have a Hitachi Seiki Lathe Type 3NE with a FANUC 6 TB control.
The display says system 6T series 992 Vers. 07
(see attached picture "version.jpg"))

The maschine does not start up.
Even before the screen displays something the red LED "Alarm Motor" on the frontpanel lights up.

I have no idea what I have to check for analysing this problem.
Any hints are greatly apreciated.

thank you very much in advance

Stefan

[lyfordln]

check for 3 phase, be sure all legs are approximately equal.
check to see if spindle fan is ok
check fuses in control cabinet

[StefanL38]

Thank you very much for your first tips. I will do that and come back with new information.

best regards

Stefan

[Al_The_Man]

Look at the input unit LED's and also check the power supply, 5v & 24vdc, you may have to remove each 24v conductor in turn to see if the power supply comes up, a load such as a shorted limit switch can cause it.
Al.

[StefanL38]

Hello,

I've been busy with other things for a longer time.

What I have checked so far is that the 3 phases are OK.

Somehow I feel like a real newbee about the electric of a CNC-control. Especially about where to find what inside of the control.

I have taken pictures of the control-cabinet of the FANUC 6T
Can somebody point me through the pictures where I have to check for:

- "input-unit LEDs"
- and "fuses in the control cabinet"

As the display comes up and shows the message "not ready"
I assume that the 5V and 24V are OK

Or is it possible that the display can show the message "not ready" and some 5V or 24V supplying is down?

Where in the cabinet do I find the "24V conductors"?

I guess these are pretty basic questions. But if a want to take the long journey to make the machine run again these are my first steps.

Thank you very much in advance for your patience with me and help.
All kinds of hints where to look or to take additional pictures to clear things up are very appreciated.

best regards

Stefan

[gridley51]

I would suspect a machine fault rather than a control fault.All my 6T`s show the not ready screen until the machine start button is pressed.Some machines have a start button and some it`s done by the control.Check none of the overloads on the contactors have tripped.Other reasons for the not ready screen are spindle and axis drive faults.
Mark.

[Al_The_Man]

The last photo is the P.S., there is also a small unit with 2 leds on and a relay, called an input unit, this checks that the PS is OK at power up, if not it shuts the power off, The green LED should be on.
If it is a short on the 24v or 5v output and not the supply itself, one way is to remove the conductors one at a time on the terminals R.H. side of the P.S.
IIRC the 24v are at the top and 5v at the bottom.
Some times it is a short on the 24vdc to a limit switch etc.
First measure the 24v and 5v to see if it is present.
Al.

[StefanL38]

Hello Mark,

thank you very much for replying so fast. As english is not my native language
(I'm german) I want to check if I understand right.

If I press the start button nothing happens.

Does contactors mean these BIG relays that are able to switch high currents?
and please excuse the basic questions - where do I find these contactors?

How can I examine the spindle and axisdrives for faults?
Maybe at first you can point me to the right chapter or keywords in the manual?

best regards

Stefan

[gridley51]

The last photo is the P.S., there is also a small unit with 2 leds on and a relay, called an input unit, this checks that the PS is OK at power up, if not it shuts the power off, The green LED should be on.
If it is a short on the 24v or 5v output and not the supply itself, one way is to remove the conductors one at a time on the terminals R.H. side of the P.S.
IIRC the 24v are at the top and 5v at the bottom.
Some times it is a short on the 24vdc to a limit switch etc.
First measure the 24v and 5v to see if it is present.
Al.

Al,if the PS or 24vdc is getting pulled down the screen does not come up.I have that fault on a machine with a 6T.Every year at so at switch on nothing happens,no screen nothing.It`s a short on the machine side,proved by unplugging cables from the connections board.I have never yet found the fault despite spending days at it.It`s a large lathe and digging about in the wiring seems to move whatever is shorting and it powers up.
Mark.

[gridley51]

Stefan,is the usual start up procedure to push the start button?
If so,you need to look for a fault on the e-stop line.
That can be caused by different faults.Usually by an overload tripping or a fuse blowing.In one of the pictures you posted it shows magnetic contacters.Next to these you can see the overloads,they have a small dial and a red button.With the power of,press all the red buttons you can see and check all the fuses.
Do you understand electrical drawings and can you use a multimeter?
Mark.

[StefanL38]

Hello Mark,
Hello Al,

thank you very much for your help so far.
Maybe some day I can help if you would like to do something
with the microcontroller called "Propeller" from Parallax Inc.

Yes I understand electrical and electronical schematics well.
I would call myself a hobbyist-EE in the field of small transistors, OpAmps and TTL-chips and I know very well how to measure voltages and currents.

But I'm a bloody newbee about this CNC-control and high power electronics.

If you would mention something like "the big IGBT on the left" I would not know how it looks like.

I want to make a suggestion: as english is not my native language
and I'm not familiar with technical terms in english. If you use them for the first time can you please use the technical term and add a short description
in easy to understand words?

Example: The "PS" (the 24V and 5V powersupply)

With "PS" do you mean 24V and 5V powersupply?

mark you mentioned "magnetic contacters". from what you explained about it yet I conclude "magnetic contacter" means a BIG relay that can switch really high currents? Is this correct?

But I have no idea what "overload" means in this case. Does it mean overload-protection? I attached a picture with red, green and yellow frames and text. Just to make sure that I understand right.

I understand what you mean with
"With the power of,press all the red buttons"

What does happen if I push the red buttons?

How do I "see and check all the fuses".

Simply by pulling then out and measure resistance beeing 0,1 Ohm or endless?

Are there any other fuses to check? Are they already shown on one of the pictures? Or would it be good to make some additional pictures?


@al: in the second attached picture I have drawn red and green frames
red frame: do you mean this part as "input-unit"? There is a green LED in the red frame and this LED is on.

green frame: I measured the voltages both 5V and 24V are present.
(so forget about the questionsmarks in the picture)

about the limit-switches I have to ask my friend who is the mechanical specialist about the machine.

There is another detail that might be important: on the front panel are
some red LEDs. The LED "Motor-Alarm" is light up. So what do I heave to check if this is the case?


Thank you very much in advance for answering

best regards

Stefan

[gridley51]

mark you mentioned "magnetic contacters". from what you explained about it yet I conclude "magnetic contacter" means a BIG relay that can switch really high currents? Is this correct?

But I have no idea what "overload" means in this case. Does it mean overload-protection? I attached a picture with red, green and yellow frames and text. Just to make sure that I understand right.

I understand what you mean with
"With the power of,press all the red buttons"

What does happen if I push the red buttons?

There is another detail that might be important: on the front panel are
some red LEDs. The LED "Motor-Alarm" is light up. So what do I heave to check if this is the case?

Stefan

When you press red buttons it resets a contact which has opened.
I think you have found the problem with "Motor alarm led".The motor has tripped for some reason.It may reset,it may not.
Now press red buttons.
You can see red buttons in your post No5,bottom left picture.These are contactors in the picture and the bit with the button is an overload.Overload is a protection contact which senses the current going to the motor.If the current is excessive in one or more phases it opens a normally closed (NC) contact which opens the contactor (big power relay thing)
Are you connected to mains electricity?

Mark.

[StefanL38]

Hello Mark,

thank you so much for helping narrowing down the problem.
Yes the machine is connected to main electricity.

I measured the voltages at the main transformator.

Main-electricity comming in from the street---main_transformator---machine

You wrote the motor has tripped. google translation translates "tripped" to "stumbeled". Do you mean the motor is damaged? Or does the motor have
a fault in the connection or wiring?

Would it make sense to start measuring the voltage at the motor and going backwards to main electricity?

Is there already flowing a current through the motor even with this Motor-Alarm-LED on?

The contactors have a black square on top. I'm not near to the machine right now so I can't take a look on the real thing. Does this square somehow
show the switching-state of the contactor. When I was at the machine the last time I pressed the red buttons but nothing happened. No click in the contactors no changes in the machine-state.

Is this alarm the spindle-motor or could it be any of the servomotors
(axis or spindle)?

How can I make the contactors switch manually? To see what changes then
or should I not do that for some reason?

best regards

Stefan

[Al_The_Man]

But I have no idea what "overload" means in this case. Does it mean overload-protection? I attached a picture with red, green and yellow frames and text. Just to make sure that I understand right.

I understand what you mean with
"With the power of,press all the red buttons"

What does happen if I push the red buttons?

How do I "see and check all the fuses".

Simply by pulling then out and measure resistance beeing 0,1 Ohm or endless?

Are there any other fuses to check? Are they already shown on one of the pictures? Or would it be good to make some additional pictures?

@al: in the second attached picture I have drawn red and green frames
red frame: do you mean this part as "input-unit"? There is a green LED in the red frame and this LED is on.

Stefan

Did you try pushing the red overload resets as Mark suggested (power off first)?

The black square in the centre of the contactors indicates when the contactor is power up, but do NOT push them in manually.
The overloads can be thermal or electronic and are operated upon excess current through the contactor and open circuit the contactor coil voltage and have to be reset manually.
The contactor supplies main motor current to the drive and consequently the motor.

The fuses can be checked with an ohm meter for open circuit, the small black square types are flag or indicator fuses and when they open a small white flag drops down to indicate they have blown, they can be opened and repaired with the appropriate fuse wire.
The input unit is as you identified and is OK with green LED.
Al.

[gridley51]

Stefan,it is difficult to answer your questions so you understand what I mean. I can only say the same as Al,but if I say it differently it will confuse you.

By "tripped" I mean the protective circuit has gone from NC to NO.Do you understand what I mean.

I can only repeat to check all fuses and overload contacts.In the picture you posted,you had typed on it OVERLOADS,MAGNETIC CONTACTOR and FUSES.That is correct.Beneath the dial with the red button on the overloads there are two terminals with wires on them.With the power off check resistance across each pair.It should be nearly zero.

Do you have electrical drawings?
Mark.

[StefanL38]

Hello Al and Mark,

thank you for your continous support.

Stefan,it is difficult to answer your questions so you understand what I mean. I can only say the same as Al,but if I say it differently it will confuse you.

I don't want to pull too much from you. So answer in a way you still enjoy it.

By "tripped" I mean the protective circuit has gone from NC to NO.Do you understand what I mean.

Yes I understand connection status has changed from NC (=normally closed) to now NO (=normally opened)

I can only repeat to check all fuses and overload contacts.In the picture you posted,you had typed on it OVERLOADS,MAGNETIC CONTACTOR and FUSES.That is correct.Beneath the dial with the red button on the overloads there are two terminals with wires on them.With the power off check resistance across each pair.It should be nearly zero.

Do you have electrical drawings?
Mark.

Yes I do have electrical drawings. I have to take a look onto them and try to find out which page is about the wiring towards the motor.

I will check the fuses, the overload-protection and the contactors and them come back with the results

thank you very much and

best regards

Stefan

[Al_The_Man]

It would be useful to know if you got any result when you reset the red overload buttons?
If they trip, you get a tactile feedback, (click) when pushed.
Or checked the fuses OK?.
If the fault is after the drive, in some cases removing the main armature connector or connection (not encoder) to the motor will allow the fault to be reset, if this is so, then it points to the motor itself.
As long as you do not try and command the motor to move, the motor DC feed can be disconnected without fault showing.
Al.

[gridley51]

Stefan,look at the elec. drawings.You will see the three mains phases coming in and splitting to go to the different transformers and the ac motor contactors.The contactors are usually hydraulics,coolant,swarf conveyor (easy to spot as it usually a reversing contactor) and barfeed motor if fitted.
That will let you see what fuses are on the main feeds.
Then,if you follow the outputs from the transformers you will see what feeds what.
At this stage you should be able to check all phases at the input side of the contactors and transformers.
That is all I can say until you have done this.
This would be very easy if Al would learn German I don`t have time.

[StefanL38]

Hello Mark and Al,

thank you so much for pointing me to the overloads.

In the meantime the CRT-monitor has a fault. I see no clear picture anymore.
Only wild jumping lines. I dismounted the monitor and gave it to a TV-expert
that he (hopefully) will repeair it.

About the motor-alarm I found something. Behind the servo-control-units there are some more overlads and contactors.

The one that has a red frame was tripped. I pressed the red button to reset
the overload and started the machine. Now in the startup sequence the Motor-Alarm-LED stays off and the hydraulic switches on (which did not happen before)

But as long as the monitor is not repaired and connected I can't tell how far
the startup-sequence goes.

I have attached a picture of the crt-monitor connectors. Do you know
which signal-standard these monitors are using? Is this simply NTSC or
any other industrial standard? or something complete FANUC-proprietary?

best regards

Stefan

[Al_The_Man]

I don't think I replaced a 6, but many of the Fanuc/Mitsubishi monitors It uses the old TTL signal low horiz freq something like CGA.
I used to use one of the old PC TTL monitors in some, they are very hard to come by now as most have gone to the dump.
What is MS2 controlling, BTW?
Al.