Citizen L32 Z2 home

[chad883]

I have a new to me 1997 Citizen L32. I bought it with a know servo amp issue. I have replaced the bad amps and they power up with no alarms. I had to replace batteries, and re home all axis. The X, Y, Z on the main head went fine. The X for the sub homed fine also. The Z for the sub moved and looked like it was doing the correct movement, but never actually homed. I am getting an NC alarm.
Z71 detector error 0006 Z

Any ideas on this? I have been told that the machine just bottoms out the ball screw and comes of to a point on the encoder, and have also been told that it has a switch to pick up home position.

Thanks

 

[Herding Cats]

Do you have a copy of the ladder and the element list? If there is a decel switch I would expect to find an X element for the input.

Hopefully someone here is familiar with that machine.

 

[chad883]

I think the book has a ladder diagram. I am not all that familiar with reading or checking the ladder.

 

[Vancbiker]

I've never seen that alarm. Looking at the manual it seems that when this alarm occurs you should have an E3 on the drive. Is that true? If it is, I may have some info on that alarm at my shop and could have a look next time I'm there (Thursday?). I got my second Covid shot yesterday and am feeling the effects. Gonna lay low for a day or so.

 

[chad883]

I've never seen that alarm. Looking at the manual it seems that when this alarm occurs you should have an E3 on the drive. Is that true? If it is, I may have some info on that alarm at my shop and could have a look next time I'm there (Thursday?). I got my second Covid shot yesterday and am feeling the effects. Gonna lay low for a day or so.

This is my home machine, so I will have to double check when I get off work from my day job. I was hoping you would see this as you are very knowledgeable. Also hoping @TeachMePlease would see this as he seems to be a swiss expert.

Thanks

 

[Herding Cats]

There are several members here far more experienced than I am with ladder logic but I will try to hit a couple basics that may help you.

X is going to be and input from machine to PMC
Y will be an output from PMC to machine

A decel switch as far as I know is going to begin as an X input from the switch to the PMC

The below is not your machine and just an example

The first pic shows X0001.7 is the Z axis decel switch. 218-20 refers to page 218 rung 20

Then if we go to that page in the second pic you can see it is a normally closed switch that then goes to R0223.0

While what I'm showing isn't fancy by any means, it would tell me for sure that the machine I am looking at has a Z axis decel switch and if I can't physically find it I need to keep looking. The info is also in the book to find it on the I/O board and back trace it.



Obviously listen to Vancbiker over me but I will tell you learning even a small dangerous amount of ladder is a super powerful tool.

I've gotten several machines cheap because the maintenance guy thought he knew everything but never even opened the ladder book

 

[Vancbiker]

The above is a great beginning point to learning some of the inner workings of typical Asian CNCs.

 

[chad883]

This looks like it does not use switches. Correct?

 

[Herding Cats]

Y0175 is some kind of output for a indicator light. (bit of useless info haha)

I'm not sure as I do have machines with absolute encoders but they all still have decel switches.

I'm not exactly sure if X0155 is a decel switch or maybe a homing button. If I had the book in my hands I could likely flip through it back and fourth and finally figure it out but I tend to muddle my way through it.

Maybe Kevin or someone else will know exactly what the deal is.

Out of curiosity what does the element list have U0039 labeled as?

 

[chad883]

Y0175 is some kind of output for a indicator light. (bit of useless info haha)

I'm not sure as I do have machines with absolute encoders but they all still have decel switches.

I'm not exactly sure if X0155 is a decel switch or maybe a homing button. If I had the book in my hands I could likely flip through it back and fourth and finally figure it out but I tend to muddle my way through it.

Maybe Kevin or someone else will know exactly what the deal is.

Ok thanks. I was looking in pic 2 line 14 says $2 (sub spindle) AUTO DOG-LESS ZERO RETURN. I assumed that meant no switch and just stroked out the ball screw, then came off to a specific encoder position? That is probably me assuming from one of the things I was told.

 

[Herding Cats]

I don't believe an axis would ever intentionally run into a hard stop to locate itself though I suppose it could be possible with tq limiting. Maybe I'm totally wrong.

Absolute encoders remember where they are. I don't understand the point of having absolute encoders with decel switches and having to home the machine. I never understood it but then again I never asked, I just kinda accepted the fact.

We will keep Vancbiker busy today

 

[chad883]

I don't believe an axis would ever intentionally run into a hard stop to locate itself though I suppose it could be possible with tq limiting. Maybe I'm totally wrong.

Absolute encoders remember where they are. I don't understand the point of having absolute encoders with decel switches and having to home the machine. I never understood it but then again I never asked, I just kinda accepted the fact.

We will keep Vancbiker busy today

Totally agree. Dont usually have to hamo machine. If the batteries die, which they did. Or if the axis is moved with power off, which it was. But not necessary under normal conditions. I also think it is monitoring torque and actual movement to know when it is at the end of travel. Mostly just a guess for me though.

 

[Herding Cats]

If you have absolute encoders without decel switches and the batteries died and the axis was moved I would bet money that is the cause of the alarm without even knowing what the alarm is. There must be a procedure to set home if it is lost.

Maybe it's the whole parameter 1815 APC APZ deal. That is a complete guess but what I need to do with my Hitachi with an absolute servo driven tool chain if it gets lost. OOPS that was ASSuming it was Fanuc

 

[Delw]

I have a new to me 1997 Citizen L32. I bought it with a know servo amp issue. I have replaced the bad amps and they power up with no alarms. I had to replace batteries, and re home all axis. The X, Y, Z on the main head went fine. The X for the sub homed fine also. The Z for the sub moved and looked like it was doing the correct movement, but never actually homed. I am getting an NC alarm.
Z71 detector error 0006 Z

Any ideas on this? I have been told that the machine just bottoms out the ball screw and comes of to a point on the encoder, and have also been told that it has a switch to pick up home position.

Thanks

Ive had the same problem some times with my sub spindle z axis on my citizen.
make sure you jog the z axis out far enough. my z axis reuqiers it to go about 3 inchs away from home. (i dotn have a x axis on my machine)
Granted mine is about 8 years older than yours. but try it anyhow
is this a fanuc machine?

 

[chad883]

Granted mine is about 8 years older than yours. but try it anyhow
is this a fanuc machine?

Mine is Mits, but I have tried that. I actually brought it all the Z+and started there. I believe from what I have been told, yours may have switches being older than mine.

 

[Delw]

most likely so. I just remember it was odd that I had to run the z out on mine that far to get it to home.

one other thing but I think its a fanuc deal. Vanbiker would know.
is sometimes you have to open up the position off you axis like 999999 home it change back the prm then home it again.
Ive had to do that on my Miyano a few times due to lost PRMS or corupted something.

 

[Vancbiker]

On a Mitsu there are a couple ways to set the absolute encoder when no switch is provided. Never saw one that dead headed the screw. The most common method has the user jog the axis to a measured distance from a reference surface on the axis to a stationary reference surface. Then set a parameter or two and then press zero return and move the axis positive. It will find the next occurrence of the encoder index pulse, then move the grid shift amount, stop and set zero return at that point. This process should be covered in your machine operation or maintenance manual.

If you don’t have those manuals and cannot get them,I can prbabaly figure out where you need to set the a is based on the soft OT parameters. It would be much easier to get the machine builder’s process though.

 

[chad883]

I've never seen that alarm. Looking at the manual it seems that when this alarm occurs you should have an E3 on the drive. Is that true? If it is, I may have some info on that alarm at my shop and could have a look next time I'm there (Thursday?). I got my second Covid shot yesterday and am feeling the effects. Gonna lay low for a day or so.

I have the E3 on the amp when I power up, but it goes away after I run the home. On this machine I have a user parameter page that I highlight #17 to activate home then #22 for Z2 then cycle start.

 

[TeachMePlease]

So what you need is the gridshift procedure.

You set your Z2 off of the face of the guide bushing with a gage block and tell the machine where it is.

I only know the basics of it though, as our maintenance department does all this. We have a written procedure SOMEWHERE... but I'm trying to find it for you.

 

[chad883]

Turned out to be the encoder. Replaced last night and all is well. Thanks to all that helped.

@herdingcats can we get this moved into the swiss node please. Might be easier to find down the road.