What would you say to this?

Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
Ok...Here is what I got from the PCB.

I have drawn the area of interest only.

Double checked the diagram and it is correct. As for J3 & J5, I think I know what the triac drives And believe me, it ain't easy to figure out which goes where.

The missing parts are Triac T1, MOV R1 and R22 ( connected to triac T5 ).
The IC 4538 is wired as a one shot I guessed, so tht part is left out, only one mono was used. Triggering part consists of bunch of resistors and a cap, sort of a time delay arrangement.

The Board is used to drive some solenoids, I traced it much later. The machine should power up properly even without the board.
 

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tom66

Joined May 9, 2009
2,595
Clearly sabotaged (the remaining resistor lead is a giveaway), but if you're going to break it like that, why not go all the way and use a mallet or something???
 

debe

Joined Sep 21, 2010
1,389
Hi, Looking at the circuit & its an embroidery machine i suspect the triacs are used to switch solenoids to shift the needles for diffferent patterns, in mechanical machines they use different cams for different patterns. I doubt this machine would work properly with those components. Just as an aside here in Australia TV current afair programs ocasionaly decide to dis able electronic equipment & call unsuspecting repairers & secretly film them to show up rouge repairers. All very good for ratings for there show. Daryl
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
@thatoneguy..
no scopes. but is on my next to get list...But for this I need a portable one. :D

@tom66..
me no break anything..me good guy...me Mr.Fixit.:D bad people every where.

@debe..
Hey thanks. Now u have said it, I think u are right. I'll check on it today.
This is not a TV show, this I can tell for sure. If it is, I'm gonna be famous :D.
too bad it is not.

Now tht the startup has been translated. it's time to get going....
 
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tom66

Joined May 9, 2009
2,595
HUH !! what fuse :confused:
Top right of board, there is a fuse holder, and no fuse. The fuse appears to provide power to the TRIACs A2 pins. Without the fuse, there will be no power - presumably, this would lead to a failure of the motors.

Fuses don't go missing. If the device was working, but isn't now, then something or someone has removed the fuse.

I just noticed another one is missing. Near the bottom left, one fuse is missing, but another one is installed. :confused:
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
Top right of board, there is a fuse holder, and no fuse. The fuse appears to provide power to the TRIACs A2 pins. Without the fuse, there will be no power - presumably, this would lead to a failure of the motors.

Fuses don't go missing. If the device was working, but isn't now, then something or someone has removed the fuse.

I just noticed another one is missing. Near the bottom left, one fuse is missing, but another one is installed. :confused:
Ohhh! the photo was taken while desoldering fuses are replaced
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
Today I decided to check for further sabotage.
Since I have the filter board, the CPU board was the only one tht has access to.

Took while and found this.



The cap has a connection to the diode cathode nearby and also to the LCD itself.
Dunno the value so checked with a 10μ, yet no improvement.
The LCD keys are locked it seems.

I think it's time for diagnostic story
.
I got a call in the morning on the day I returned to Male'
I was really tired & did not want to get to work but rather sit down at my PC and enjoy re sizing the photo's of my vacation. But being short on money I thought I will make a quick buck with the job.

I had no idea what I was getting myself into.

I will use the company for the company that uses the machine.
The old guy who is the so called maintenance guy, is from Maldives, Addu atoll
The Operator who operates the machine, is from lanka.
The company has a Manager and GM, whom I dealt with.
I need to the keep the identity secret.

The call came from a friend of mine who is a ref tech. He was there to get his island school badge's order done. That morning there was a major blackout. The whole capital was without power as far as I know. power came to my house with in the hour, but it seems to them it lasted for hours.

When power came the machine won't respond, so it seems.
My friend was there, so he checked the fuses since he was a friend of the old guy. Since the machine was CNC, it was out of my friends league.

Ring......Ring......Ring......the manager is on the phone

I got to go ...cops are at the scene of the crime :D

brb
 
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retched

Joined Dec 5, 2009
5,207
This is a first, I've heard of letting the smoke out, but, letting the parts out? :)
AAWWWW!!! Time for a SONG:

Who LET THE PARTS OUT?? WHO, WHO, WHO?

--my bad-- ;)

Rifaa was there a jumper soldered in, or is that just part of the "missing" parts leads still on the board?
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
That good for nothin son of a Jackal geezer

He is pinning it on me.

As of now I am really mad. I need to cool down and think this thing thru....

and yes, i have emailed dahao
 
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tom66

Joined May 9, 2009
2,595
That good for nothin son of a &%&*$$.

He is pinning it on me.

As of now I am really mad. I need to cool down and think this thing thru....
Did you take pictures of the board before? If you didn't maybe that's what you should have done...
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
Did you take pictures of the board before? If you didn't maybe that's what you should have done...
I really dunno how to tell what happened and I don't think I should talk about internal affairs of a reputable company.

I got the pictures of everything, I was updating the thread when the call came. I have evidence of sabotage of the XY motor driver connections too.

Right now I am not in the mood to talk about this.:mad:
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
Well! Vacation was soothing and fun....it was the calmness before the storm ;).

I was like :eek: after I heard the geezer's story. He was like the only man for the job. And the machine is like piece of glass tht only he knows how to take care of.

The funny part is he couldn't tell the difference between a stepper driver and a transformer. I asked him after pointing to the stepper driver assy, "what is this". he replied, damn proudly ...."Transformer"...
He only see's one motor driving the table, in all these years he missed the one in the middle back where the second motor is installed. talk about ignorance.

Furthermore this guy confirms tht it has cable and fuse faults. He never realized that he indeed is telling me what he had done.

Always said tht he can get the boards from Srilanka. What he does not know is tht dahao does not have a branch in lanka, infact very recently they opened a new branch in Mumbai.

Dahao has strict regulation to protect their products. Any one can see the criminal case tht was done due some Chinese guy duplication there brand and name. It's all on there site.

This guy started to poison the mind of the owners from the very beginning I showed him them missing components. Now I regret ever sharing the findings, cause he was the one who did it
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
Due to request from certain personal I am updating the thread.

Work is on hold till the investigation is over. I am giving my only free time to the cops to explain my findings.

Cont

I went to the factory location with my fluke only since I dunno what to expect. All I heard was a badge making machine with circuit boards.

To my surprise the machine was huge



It can make around 5 badges simultaneously on it's own. It's almost like an engraver tht I am making, except much bigger.

The needles moves up/down and sideways I think. And the cloth is mounted on a table that moves along the axis. So it has a X motor and a Y motor. Which are 3phase stepper motors. Quite big too.



The Motors use 3 phase and has 3 wires plus position sensors built in. I can say this due to the fact that there are couple of more wires going into the motor other than the 3 drive cables.

The machine can accept floppy or USB drives with badge or whatever drawing that needs to be sewed. One push and it does the job with in seconds or so.

I was greeted by the operator and the old guy, whom I thought was an authority body. Since he was smart and all.

I asked about the problem and old guy said the machine won't work after the power blackout. He and my friend had checked the fuses at the back.

So, Naturally I too went to the back and saw the back cover removed and I can see 3 chassis mount fuses. I checked them with the meter and they were OK.

It is my nature and the way I work that I ask a lotta questions about what I am fixing. The Old guy's story was remarkable. He said that and I quote

"I bought the machine from abroad and I sold it to the company."

Which lead me to believe that he has some authority over the machine which I found out later was a huge mistake.

Funny thing is that he is repeatedly telling me that "that transformer is not getting any power". I asked him what transformer since I cannot see any.
He pointed to a small cabinet mounted next to the CPU Cabinet.

I said to him..is that a transformer ?. I was giggling but he could not tell. He said, yes, that transformer is not working. It never struck me then why he is saying it so positively, rather I found it funny for the fact he couldn't tell a stepper driver from a transformer.

So I went along with him and checked it's supply lines and found out that there is no power coming ( 220VAC ). I asked him where is the wire connected and he showed me the CPU cabinet and yes the cable is terminated inside the CPU cabinet



From the above picture to ur right are labeled from 1 to 13 is the terminal block which has 220VAC only. Connections are paired. One goes to the stepper driver and the rest goes inside.
I probed around since there is label at the bottom stating the pair voltages. Each pair is a 220VAC line. Only the one going to the motor was dead.
Fuses are OK so why the heck no power. I have to go deeper.
So I left saying I need to bring some tools to do this, and old guy said OK.
So me and my friend left.
 
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Thread Starter

R!f@@

Joined Apr 2, 2009
9,918
I returned with some power tools and started to remove the PCB, which has a 12V and a 24V DC bridge and caps with fuses. And also 5 triacs, sorry, 4 triacs. I removed the board and the connectors and pulled the internal assy and found out that it has a transformer inside the cabinet.
Further more I found a broken termination



The disconnected wire was an input to a line filter that u see above. It provides the 220VAC to the stepper drivers.

Problem found. Like I thought, a quick buck. So it seems.

I knew that filter is inline with the steppers incoming. But I have to solder it, tough luck, I did not bring the iron.

Al this time the operator was helping me and old guy is blabbing nonstop. As I remember he says it has a simple transformer fault and the fuses are OK and we need to check the connections and yadi yadi yada. I some how got irritated, so I just ignored him.

In my mind, this is a simple broken wire and I have to go home again to get the iron. And since my friend had left for an errand, I called him and he said he will take some time. Now I have some time to kill. and since I have taken the PCB I thought I will check the fuses on it too.

This lead me to look closer and found the snipped of components plus the fuses were underrated. One fuse was blown cause it was a 3A one. But the labeling says 15A.
That's strike two. And yet I did not think it as too much of a problem since these things a pretty common to me.

I have seen so many mishaps that I never for once thought it was a sabotage.
But I did show the missing component area and fuse to the operator and the old guy. I did asked him tht who touched it, and yet the old guy simply shrugged and said no body, it is as it is. Which leads me to some confusion. But I said tht there shud be a component there, whether the machine worked or not, I dunno.

It never occurred to me to inform the owner then. And since the old guys story was going haywire and something like...nobody can fix the machine, and he has to get part from lanka and I really cannot remember what but it just hit me that this guy is up to no good.
It's then I asked for an authority figure. After a while the manger came to me, whom I have a faint memory of, he has plain ol' youth just doing his job attitude and did not know much about anything concerning the machine, other than that he has a lot of orders to finish and he wants the machine to be up and running ASAP.
So I said that I have to take the board and find out the missing components, yes, I said missing components, but it never struck the manager cause he has no idea what a component is. So naturally he said OK. take it and fix it.

So I came home and what happened is explained in earlier posts.
The resistor was the difficult part. I had to buy it next day. I managed to find a triac and a mov of the same ratings. In order to find the resistor value I had draw up the schema....I was up all night. That's two night without sleep. First night I was at sea.

They kept calling but due to not knowing what to put there delayed.
Next day I packed everything. I mean everything. Took off to the shop, bought 2 pc 10W resistors. I did not solder the missing ones, since now I know that the machine will at least work without them, only catch is that it will miss a stitch or something. The triac has nothing to do with the stepper drivers. But I desoldered the via holes, made them ready to be soldered.

So there I was and the manager and everyone was there. I soldered the disconnected wire to the line filter and checked. Power is now available to the "old guy's transformer" I can measure 220VAC at the stepper terminal. I put the board without the components and powered up, after replacing with proper fuse ratings.

Nothing. Monitor lights up but the table won't respond....old guy saying still no power to the transformer..

I got really confused, so soldered the missing components at their presence, mount the board and powered up.... Nothing ..same as before.
I got blank, manger went to his office and old guy is just sitting there couple of feet away. Shaking his head.

Looked every where, removed the front cover exposing the CPU board and it's PSU. Poked the Meter...everything is there, but no movement.
Old guy said....check the transformer....
I thought what the heck, so unscrewed it and took it out see below..



Upon inspection I saw the main cable loose. A little tug and it came out. I thought a simple loose connection. So I took all the cables out of the left one, trimmed them and soldered the tip and screwed them back really tight. I did not touch the right driver yet.
Powered up and yet the same. The Hard ware isn't even budging or initializing at all. I though I'll check the other one for loose.

And this is when I found out what was really happening





See the two pictures..the motor connections.

The Blue wire is no where to be seen... I was like what the :eek:.
Identical motors and drivers but one driven with two wires. no way...routed the cable to the motor and found this



Blue wire or rather 3 wires are used but why the heck it isn't terminated.

Never gave a second thought ( mind u tht I am always snapping pictures before and after) stripped the right motor cable and found the the third (blue) cable inside.

From that point I realized what was really going on.

I stripped and connected the wire but did not power up. instead packed up everything, removed the Triac PCB, and went to the office and requested a meeting with the machine owner.
 
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