Z limit switches not working on X7...

[als]

Does anyone know how to make the limit switches work for the Z table? I have limit switches for both up and down, they are wired up and continuity tests fine. When I go into Axes Control and Reset Z, it will move the table all the way down until the limit switch is hit. (Good, right?) But then if I use the keypad to move up or down the limit switches are completely ignored.

Also, even if I start with the table in the highest position, and run the Axis Control|Reset Z, when I try to move back up the table only moves 1/3 of the way before stopping and I have to hit reset to start moving it the rest of the way -- again only another 3rd, so it takes 3 resets to move the entire distance.

Did I just waste time building in the limit switches? Is there a way to get the full motion from top to bottom? (I changed the range from 500 to 1100, this did not help.)

Thanks.

[Tech_Marco]

3 things you need to pay attention when dealing with power Z table:
1) Only 1 limit switch is required as the range is (limit) is control by software (soft limit). And the limit switch is supposed to be installed at the top of the Z
2) You need to calibrate the 'um' for the Z axis. If not, 5000 or 1100 means nothing to the Z table. Same technique as finding 'um' on X or Y
3) The initiation of the Z table is (assuming it is idle on top prior to power): Move Up till the limit switch is triggered, then it down for about 20mm, then it move up again at focus point (if you have that set up. If not, it stay right after disengage with the limit switch)

If the Z was somewhere but not rest at the top, it move up when power is turn ON. It trigger the limit switch, then back down for 20mm, then move up again and stop below the limit switch.


Marco

[als]

2) You need to calibrate the 'um' for the Z axis. If not, 5000 or 1100 means nothing to the Z table. Same technique as finding 'um' on X or Y
Marco

The technique that I used for X and Y was to "cut" a 100 mm square and then measure it with the calipers and enter the expected vs. the actual. How do you instruct the machine to move the Z table a certain distance?

Thanks.

[Tech_Marco]

Read the distance from the LCD display. You move the Z table say 50mm down, than measure the actual distance it travelled, isn't it enough data collected to calculate the UM?

Marco

[als]

Read the distance from the LCD display. You move the Z table say 50mm down, than measure the actual distance it travelled, isn't it enough data collected to calculate the UM?

Marco

No, that isn't working. The LCD says 0mm for the point where the bottom limit switch kicks in. Measured with the caliper from the frame to the table it is 67.45mm. When I raise the table (using the up-arrow) to 59.8mm (couldn't get an even number), it only actually raised it to 64.18mm, so a total of 3.2mm. When you put that in the expected/actual dialog you get a um/pulse number somewhere around .3 IIRC, and if I set the value the table no longer moves at all.

I've tried every dip switch combination I could think, and finally went back to the same switches used for X (1/16) because the table moves well with those settings given the conditions I outlined at the start.

Do I have the motor wired wrong? It seems like if I did it wouldn't move the table up when I push the Z up arrow, and down when I push the down arrow...?

Thanks.

[als]

Any ideas on this? Did I do something wrong? Or is it a bug with the DSP controller? Thanks.

[Tech_Marco]

There is nothing wrong with the Z axial. We're using it frequency. Always think the connection/setting issue before considering the 'bugs' As I mentioned before (many times), the Z table do not need the bottom switch. You install the limit switch at the Top of the Z table because the bottom (traveling distance) is controlled by the software through Z distance.

What you need to do prior to fine tuned the traveling distance is to make sure that the Z move correctly with arrow Up and arrow Dn key. You may turn off the "Homing" for the Z on LaserCad when testing the Z. All traveling distance can be found on the LCD screen.


Marco

[als]

There is nothing wrong with the Z axial. We're using it frequency. Always think the connection/setting issue before considering the 'bugs' As I mentioned before (many times), the Z table do not need the bottom switch. You install the limit switch at the Top of the Z table because the bottom (traveling distance) is controlled by the software through Z distance.

What you need to do prior to fine tuned the traveling distance is to make sure that the Z move correctly with arrow Up and arrow Dn key. You may turn off the "Homing" for the Z on LaserCad when testing the Z. All traveling distance can be found on the LCD screen.


Marco

As I mentioned, the UP arrow moves the Z table UP, the down arrow moves it DOWN, so I think it is wired correctly. Can you comment on how the DIP switches need to be set on stepper controller?

I can remove the bottom limit switch. The problem is that if I uses the distances on the LCD screen as you've suggested to calibrate the 'um' for the Z axis, it produces a number so small that the table no longer moves properly.

Thanks.

[Tech_Marco]

I will either use 1/8 (preferred) or 1/16 for the micro-stepping
What is your current setting?
What kind of Z table are you using? What is current setting? I found no information regard to your table


Marco

[als]

I will either use 1/8 (preferred) or 1/16 for the micro-stepping
What is your current setting?
What kind of Z table are you using? What is current setting? I found no information regard to your table


Marco

I'm using the Z-table you sell (http://www.lightobject.com/Power-table- ... -P722.aspx).

When the um is set to 6.33 the table moves up and down at a good pace, but will only move 1/4 of the total distance without shutting off the machine and turning it back on. The switches are set for 1/16.

-Andrew

[Tech_Marco]

You need to find a 'um' to match the actual traveling distance, just like what you did on X &Y
The traveling distance is set on the "Z" parameters under LaserCad. As long as the Z is moving, you need to play around with the setting.


Marco

[als]

You need to find a 'um' to match the actual traveling distance, just like what you did on X &Y
The traveling distance is set on the "Z" parameters under LaserCad. As long as the Z is moving, you need to play around with the setting.


Marco

Okay, thanks. I will try just entering different values. I thought the actual verse expected would calculate it, but it does not.

[Tech_Marco]

It should work. You just need to measure the actual distance it moved and use the um calculator to find the value.

Marco

[als]

It should work. You just need to measure the actual distance it moved and use the um calculator to find the value.

Marco

Yes, I did that. The LCD display would say it moved 50 mm and in fact it only moved 3 mm, so it produced a super low um value. When I put that in for the Z axis, the table would buzz but not move.

[Tech_Marco]

In that case, multiple the distance to make up a longer traveling distance


Marco