jv3 160sp blank print

[artbot]

back in september 2012 i had an issue pop up (intermittent) in which my jv3-160sp would run a print mechanically but all four heads would not fire. these are all new heads. the issue was discussed in this old thread:
http://www.signs101.com/forums/show...-print-just-went-blank!&highlight=blank+print

i've now sold the printer. i clean it up, get it ready for crating to remember "this printer was never diagnosed and repaired".

most recent history (2012):
-three new heads installed
-new/rebuilt slider board installed

symptom:
-can occasionally just go blank during print
-when in uni-directional, it seems to add about 10" distance to the left before returning
-issue disappears/appears with no cause

(otherwise the printer acts completely healthy)

parts replaced:
-new encoder reader replaced, no change

 

[Solventinkjet]

I would double check the encoder sensor height and make sure the encoder it self is properly weaved between the metal clips that hold it. Sometimes the encoder pops out of its holder and can cause it to pop out of the sensor as well. Other than that my best guess would be that the trailing cables are damaged, loose, or otherwise compromised in some way causing the signal to be interrupted either from the encoder reader or to the heads. Check to see if the trailing cable is moving smoothly or if it is jumping/jerking around when the head moves back and forth. It could be a main board but it sounds more like the signal from the sensor is being cut off somehow.

 

[artbot]

just raised the encoder reader. it was set and a lower-most position. no effect.

inspecting the trailing cable, looks good. there was some minor edge bends as the cables enter the slider board. this is from installing them and the edges getting roughed up a bit. i moved them around a bit. no effect.

UPDATE:

after waiting a few hours, it worked. then on the next print did not. so perhaps some kind of???

 

[Snydo]

I had a bad firewire cable do some wonky stuff similar to what your experiencing one time on our 160sp when we had it. Good Luck.

 

[artbot]

i'll check that out. thanks

update: tried it, although with an even older firewire cable. no difference. odd that the whole machine performs so "robustly" but no heads firing. it is completely unaware. this printer never hesitated to give an error code for just about
anything odd. but not this.

 

[Samurai_Screwdriver]

Hey Artbot,

Robert is correct, could be encoder related, especially as it is intermittent. When its in its non-working phase, go to the #TEST menu and run the ENCODER TEST. When its done you'll get both an "M" number (Motor Encoder) and an "E" number (Linear Encoder). If the E number comes back as zero then the Encode Sensor signals are not making it to the Main PCB. Change the Encoder Sensor and re-run the test. I believe I have some used sensors. PM me if you need one.

 

[artbot]

thanks for the info! i'll try that. i have a spare encoder sensor here to swap out for comparison.

 

[artbot]

okay...

did the test and i did get M1960.9 and E0.00 value.


1. put in the new encoder reader (believe to be new)
2. do the encoder test
3. get M1960.9 and E1654.4
4. do encoder test
5. get M1960.9 and E1870.4 and Error 08 Encoder
6. to encoder test
7. get M1960.9 and E585.8

so i decide to go read my manual to get a read on these stats and error. one thing i'm curious about. when starting the encoder test it mentions "Indicate the movement distance that the carriage is
moved". is this something that i enter? the manual shows blank asterisks, i have a value as soon as i get to that window. is it possible that this test is failing because my value is too high? how does is this test properly performed?

(see attachment)

 

[Samurai_Screwdriver]

So the size that you enter doesn't really matter all that much - it's mostly useful if you're trying to determine whether an Encoder problem is occuring nearer to the Capping Station or further out along the strip.

The "E" number of zero indicated that the Encoder Sensor wasn't reading the strip at all, so changing it makes perfect sense. The reading you got with the new Encoder looked pretty good (the E and M values never match exactly due to the Compensation that is made by the 500mm Square adjustment) but then the subsequent tests seemed pretty erratic - this makes me wonder whether the tracks on one of the 40-pin ribbon cables responsible for carrying Encoder Data gad has an intermittent break in it or is worn through and is grounding out. Mimaki never published specs on which cable carries what but I have a compltete used set if interested.

Also, you might want to double check that thr new sensor installed does nit have a dodgy set of wires on it.

 

[artbot]

GREAT INFO! will look at all these suggestions.