Avalon VLF 60XXT Autofocus problem


We have an Avalon VLF 60XXT CTP that has an autofocus problem.

On OCT it's : Imaging: Autofocus controller fault

Error C0=53030580 C1=00000066

when autofocus starts: write af:: ss_cnt= 1, onplt_cnt=81, offplt_cnt=0, res_pos = 169

Now i know that if ss_cnt is 0 or 1 that means that it's a fault at the start of the autofocus sequence. We did encoder test in unidiag, reading was between 19 and 24, which is <50, so that has to be good. Also at the start of the machines, the report for mpos is always around 19 (afinit: mpos = 19)

Couldn't do the s-curve test, cause it's giving message = S_curve not found.

Since it's happening at the start of the autofocus, i'm assuming the only thing left are either the illumination module (30mW 655nm laser) or the autofocus driver board. The driver board we re-flashed, that didn't help.

Any ideas? Does anyone also have a service manual concerning the autofocus part of the avalon. In particular, how to properly do the s-curve test etc... ?
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Armya Inc

Well-known member
Why not thinking simple:

I removed my comments, I thought it was Avalon LF.

If the chiller is on 20 that is fine. Ignore the comment on the interlock.

Do you get the Autofocus Controller fault during boot up sequence or the machine completes the sequence?


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Always good to start simple.

For the chiller, it's set to the same pressure it's always been. Though the machine did have another error many time before. Error number S0CA0 (Hardware: Problem with GLV PFM). Though the chiller is perfectly fine. Checked many times. Proper pressure, so good flow. Always 20 degrees.

From what i understand in the imaging head there is a flow switch, not even a pressure sensor.

The covers are closed and interlock indicators are lit up 1 through 7 on the front of the I/O chassis, with the interlock release switch in the lock position. Otherwise the machine cannot be started. No one touched the motion override key on top of the I/O chassis.

Do you mean an interlock key on the drum cover or?


Ok, thanks. But anymore ideas?

Edit 2:

No, no autofocus faults during machine boot up sequence. Only after a job's been started. Happens on 10% progress mark on OCT. See below:

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Wanted to ask, if anyone knows, on the autofocus driver board,the resistance between testpoints TP1 and TP18, can it be below 1 kOhm ? From what what i know usually it would be over 1K and between TP3 and TP18 below 1K ?

Unfortunately the information necessary for calibration of the potentiometers on the illumination module (AFIS) is missing. (the sticker with Quad Loop Gain, QD Lp Gain, TP1 and TP3 resistance). So i have no way of knowing if the adjustment went out of tolerance.


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All the info i know about our illumination module is that it's a 40mW model, with a few labels on it- IM330, SW 8,6,3,1

Edit 3:

Sorry made a mistake with the machine name, it's 50 XXT, not 60 XXT.

I was also doing some comparisons to a working Avalon 50 machine we have sitting next to it. Was performing a quad test on the 4 element photo diode (quad cell) located in the illumination module (AFIM) that detects the reflected red laser beam off the plate/drum travelling back through the optical path that generates astigmatic elliptical spots hitting the sensor.

Comparing the quad readings to our working machine, i noticed that the relation between A - C and/or B - D differs in every test.

Take a look, a comparison of reading from the quad cells on both 50 XXT and 50 machines:

Could it be a defective illumination module?



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