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Juki 740 troubleshooting - Component Standing

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Juki 740 troubleshooting - Component Standing | 4 August, 2008

We're running only our second job on our newly aquired Juki 740

The problem I'm having is as follows, I program the locations, component info, pick info, all fine. When I have the machine measure the component, everything comes up fine, it returns the part to the tape perfectly.

When I go into production mode, the machine picks up the component (0805 resistor), heads to the first location, stops over the location gives the error message "Component Standing" and rejects the component to the tray.

In the expansion menu, I have tombstone detect, autocorect pick off. I cleaned the LASER lenses, remeasured the part OK, I can't find the error.

Can anyone point me in the right direction to help diagnose?

There seems to be a quirk with the machine that I have to use the embossed paper ting and I have to it at 90 degrees for the feeder pickup although the tech told me the feeder is at 0 degrees (ie, if I program the pickup at 0 degrees it measures an 0805 width as 79 and length at 47)

The user interface is a little choppy "Now please to shut down machine, OK?" So any guidance would be greatly appreciated.

Thanks, Rich

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Juki 740 troubleshooting - Component Standing | 7 August, 2008

With Laser centering nozzle condition in terms of slider shafts have to return to same position every time. Please check condition of nozzle and make sure slider extends to full position. If slider sticks it can generate errors as the component appears at different scan height.

Also Laser could be problem, do you know how to use laser diagnostic ?

I recommend not to clean laser with solvents or liquids that deposit residues, only use small amount of IPA , watered down maybe if you suspect laser is dirty. Try and use only dry clean after this - microfibre lens cloth etc to remove dust etc.

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Juki 740 troubleshooting - Component Standing | 8 August, 2008


You were right on the money, the day after I posted, I recalibrated the LASER height .020 off on LA head, .01 off on LAIC, running perfect now.

Secondary issue is a flicker on the monitor, the grid stays up after teaching XY coordinates, sometimes the grid stays on the screen, seems silly, but could it be a sticky relay? I would think it's controled digitally, but the problems have all the characteristics of dirty relay?

The image is fine, it's only the grid overlay that flashes and it stays on the screen sometimes after pressing enter on the HOD.

Thanks for the good advice on the LASER height, you had it nailed.

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Juki 740 troubleshooting - Component Standing | 18 August, 2008

Great to see running.

The Vision Monitor Video comes from the Vision Processor Card, including overlay info, grids etc depending on mode you are in, like teaching etc

Why is is on still I can not say, could be software version, there was several versions over few years etc.

The earlier your machine rev the older the software I suspect. The rev of machine is on label near serial number - Juki colours in one of the letters - A,B,C,D..... If all not coloured is REV A machine, if A coloured in, is B Rev etc.

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