Thread: Deckel FP2NC X axis run away

Another way of thinking about +- 10v control, is the servo amp does nothing in its whole life but try to make zero. The tach is wired opposite the input, so envision it as the tach and control signal grounded together and when you measure the two loose leads the servo amp tries to make that measurement zero volts.


If there were not an easily changeable parameter for direction control for the axis, I think one could reverse both the tach and signal wires at the servo amp and that should cause it to run the other direction, but possibly it would csue other issues, as I think the correct way to do it is through parameters

No set able parameters in this control as such.
There are DIP switches on the axis display boards, but no information as to what each does, just a truth table of how to set them for a specific machine and axis....
It is possible to kill the axis card (don't ask me how i know this) by getting the DIP switches set wrong for a machine or axis....

Changing the wiring is problematic...wires are quite fine either in the 9pin Heidenhain scale connector or the connector plug to the axis card....
Easiest test is to physically flip the scale....Takes like 10 minutes to verify if this is the issue.

Seems the issue here is not a direction issue in running the servo, but rather an issue in reading the direction its moving.....Swapping the servo card inputs won't change the direction
indicated on the CRT by the move, it will still be incorrect...
Cheers Ross

Okay,
I am making progress. The X Axis is under control. Turns out that a dip switch was not in the right position. The Orange book that I have shows NZP x axis SB 6 as OPEN for the FP2NC.... the note says that FP3NC and FP4NC is is "not Open" the German note says "Zahlrichtungswechsel" which translated means "Change in Counting direction". I changed it to "not Open" and now the X-axis behaves as it should.
The control shows a positive in the X axis Now!

I tried to reference all axis. Y&Z are fine. The x axis moves smoothly and hits the E stop. Does not find reference at all. Any ideas here?

Thanks everybody for your knowledge.. the combination is leading me to the solution!
Michael

perhaps it is referencing in the wrong direction, probably another switch?

Cool.....Glad you checked the settings....
"X" should reference in the Plus direction.
Adjustment of the read head in order to find thee reference mark on the scale can be tricky. Had a "Z" scale that i sent out to a shop fro seals and cleaning etc, and when it came back it would not reference.

Does the slide slow down its feed rate just before it hits the limit switch? (might have to turn it up the feed rate to see this happen)

Can you tell us who did the scale servicing?

Are there multiple limit switch cams on an FP2NC? My Dialog machine has a separate cam to close a switch when the axis is close to the home position.

The axis does not slow down before it searches for the Reference point.
I had the feed rate over ride at 10% and it still misses it.
The slide moves away from the control panel (right to left) for the reference point... Correct?



These guys did the rebuild on the glass scales

Michael Snider
2044 West 20th Street
Erie PA 16502
814.454.5559 - Office
[email protected]

Reference move direction is correct...
Don't think you will see the slow down at only 10%.

Each axis has three switches for end of travel in each direction,
The first one encountered is one that slows the feed rate so the slide won't crash into the limit switch at full rapid.
Next there is an end of travel switch
Then there is a switch for over travel. That one shuts the machine down (E-stop)
Try moving the "X" using the manual feed buttons coupled with the rapid button going in the plus direction.(table moving away from the operator)..Run the rapid at 100% ....
Slide should approach the end of the travel, then slow down and then stop .
At the end of the axis read out you should see an "E"...depicting end of travel....
If it does not slow down perhaps that switch is not functioning.

The original scales for these machines have only one file marker at each end of the scale, unlike DRO scales that have file markers like every 10mm .
Guys that work on these scales sometimes don't get the read head adjusted so that it reads the file marker reliably...have had this issue in the past.
If the control initiates the move to set the datum (mode3) and it slows on approach to the end of limit i would put money that the scale is not working properly.(Not seeing the reference point)

Be advised that you really don't need the reference point! It is only of value to recover in the middle of a program should you have a power failure....

You can set the program zero anywhere you like, it makes no difference....If you have a feature or edge that you can dial up on your fixture or part to program from then the datum set is a waste of time.
The way it works is that you initiate the reference...machine moves the slide to the plus end of travel where it locates the end reference mark on the scale. Control sets the axis readout to
0.0000.
You then move to the start point of your job using jog and manual feed buttons....Dial in and record the move value from the datum....You must keep track of this value...(program notes)
then you set the register display (Mode2) to zero in most cases...this is the start point for your program. Should you loose power or begin work the next shift you reference the axis, do an MDI move
(Mode7) using the recorded move value that you noted, and then reset the start point to zero (or what ever you like, depending on how the part is programmed)
Point is you just go directly to the reference point on the part and set the control display to zero directly....No need to reference...it doesn't set any hidden registers or values....as soon as you reset to the part its
all the same. Maybe i am missing something, but i rarely use the reference.....Becomes more important if you are running multi parts where the fixturing might give varying positions of the blank....

If you have a scope you can read the output of the reference on pins 7 and 8 of the connector...must do this inline with connector connected.
LS 803 scales should have 4-15 micro amp output pulse.
LS903 scales (what the machine should have) is a 5 micro amp pulse

Additional resource fro scale repairs:

Welcome to A Tech Authority

Cheers Ross

Thanks Ross,
I was aware of the reference point not being relevant to the machine function.
The first thing I tried was G92 to set new coordinates.... then I read some of the programming manual.
I guess they didn't have G92 back then....
I have to relearn and early programming system. Most of my experience is Siemens 3G, Fanuc 15m, Fanuc OM, Okuma OSP - 5000
That was many years ago. I haven't touched a control in 20 years!
I was reading the manual and they showed how you could save programs on a Cassette tape!
or a Tape reader if you prefer.... this is an old control.

Any favorite programs for cutting circular bores or od's?

And thanks again for the help.
Michael

The Dialog control has many of the features of more modern Fanuc based controls, but the G-codes are often different.
G54 lets you set a new co-ordinate for any axis written in the same block.

Not sure about the early versions, but on the later Dialog4 there are canned cycles for milling pins (G75) and pockets (G76) and also G86 for using a boring head.

Biggest adjustment you will have to make on a Dialog 2 is that you can only have one program in memory at a time, however there are work a rounds.
Member here, "rimcanyon" has a D2 and gets ti to run multiple programs by making the additional as sub programs. Never done this but might drop him a pm.
The other thing about the D2 is that the cutter comp is only local to the block where its called....so you need to call cutter comp each and every time its used and have to define the comp value each
time. Later controls are more conventional in this respect...D4 has cutter comp that is global, and once a tool (T) is called it is in effect till its superseded...

D2 does have some canned cycles. Important to remember that all depth moves (Z, or Y) are incremental from where you start the cycle.
No RS232 on the D2,sorry,so loading programs is tedious. The audio tape thing is interesting, never tried it.

The Deckel documentation is pretty good. The operators manual has lots of examples of programs and cycles, with your experience you will have no trouble getting up to speed on this control.
Just have to turn down your expectations....
The user interface on the other hand is excellent.....no screens to page through to find what you want, everything is available through the rotary mode switch, and it even makes sense.

Nice to have you on board...enjoy.
Cheers Ross

I run D2 on my FP2NC, which I bought from Ross. It has an X axis scale which is not able to locate the reference also, but I do not use that feature.

I got RS232 working by moving the wires that go to the tape jack to a DB9 socket. If you look through old threads the instructions are not hard to find. The computer connection is not currently working, I installed a USB converter and I think it has failed, so I will need to solve that the next time I want to download something. I typically use mode 7 for most of the work I am doing, or I write a small program on the fly, but I have a big project coming up where I will need to mill a graphic design, that will require a computer download capability and possibly a Perl code generator...

For programs I write on the fly, I just append the new program at the end of the existing program. I start each new program at an easy to remember block address, like 100, 200, 300, etc. Each program ends with an M30, and in mode 8 or 9 I just type N 500 or N 550 or whatever the starting block is for the program I want to run, before pressing the control start button. Sometimes I have 10 or 15 programs in memory. Often many programs are similar with sightly different parameters (one of the motivations to write a Perl code generator). I find Dialog to be a very concise language to program in, so even relatively complex jobs are quite short (unlike the programs generated by CAM/CAD). The two main limitations I find with Dialog are 1) you can only rotate the axis in one plane, xy, xz or yz (i.e. you cannot rotate in xy followed by a rotate in xz) and 2) there is no way to parameterize a program except for tool presets (i.e. you cannot store a radius value then use that value in a G02).

If you have any questions I’ll do my best to answer them, but I don’t check this forum on a daily basis, so email is the best way to contact me.