NEW CHINESE LASER BLEW UP WHEN PLUGGED IN HELP NEEDED PLEASE

[buddydog]

And BTW, at least on my 110V K40 machine, there IS a fuse inside the IEC plug. Not very obvious how to get to it, but it is in a tray you push out under the IEC plug. You could check that, too.

And the fuse could make a flash and a nice bang also. If it's blown don't just replace it and repeat the carnage! Something made it blow!
Just went and looked at my supply (the all-in-one unit) and the only fuse I see is on the circuit board near the input. Retro are you saying there is a fuse inside the cord connector on the back of the machine? I don't want to move my machine but looked with a mirror and there does appear to be a small cover on the bottom of the receptacle. Does that pull out or open? Good to know!

[Retroplayer]

And the fuse could make a flash and a nice bang also. If it's blown don't just replace it and repeat the carnage! Something made it blow!
Just went and looked at my supply (the all-in-one unit) and the only fuse I see is on the circuit board near the input. Retro are you saying there is a fuse inside the cord connector on the back of the machine? I don't want to move my machine but looked with a mirror and there does appear to be a small cover on the bottom of the receptacle. Does that pull out or open? Good to know!

Well, we all know that what is or is not present on anyone's particular machine varies a great deal even with the same model from the same supplier. But on mine, yes, there is a fuse inside of a tray under (or above) the IEC plug on the back. There is a hole on the back side of the plug (meaning from inside the unit) if you push a screwdriver into there, the tray will pop out and reveal the fuse, which is 10A on mine.

Are you able to see the pics above?

I have mine out still because, if you remember I have the whole thing torn down. I will be replacing the AC wiring with 14ga wire since I am adding two switched outlets to the back. I will need to bypass this fuse and provide other fusing inside my unit. The pics are of the plug that was installed in my K40.

One advantage for everyone else is that they get to see inside the machine in places they wouldn't see without tearing their own unit down. For example: there is a connection for a fan inside my power supply (MYJG40W), but no fan. I installed an 80mm 24V fan while I had it apart and added thermal paste and copper shims to the heatsinked parts.

[buddydog]

Wow. Didn't see that coming. I would have found that in a couple of minutes with a continuity check of the line but I had no idea that had a fuse in it. Good call Retro! That will be nice information to file away for future use. Mine is exactly like your picture and on the bottom. I would bet money the original poster's fuse is blown and that was the "bang"!! Hmmm. I bet the "manual" doesn't mention the fuse...Ha Ha...AND I have to say I didn't think these things had any safety devices on them. I'm impressed. What is sad is if the Chinese would provide even a basic wiring diagram for these things they could save a lot of hassle, money, time and good will. You notice there is never (with the K40) any pictures of the insides of the electronics bay.

You are so correct about the various parts used in these things. Almost no one seems to get the same tubes or power supplies. Still these (gen4?) have to be one of the best bargains on the planet.

Today I will be putting an Icelandic horse on a square Libby glass from the dollar store for my wife to give to a friend when they have lunch Friday. I'm working on my supercub aileron's today and will be using the cardboard glued together stack forms I lasered and made to give the leading edge "form" while riveting them in position. Making the forms with a jig saw would have been tedious and inconsistent, But the lasered parts are perfect and should yield a perfect form!

[odinsminiatures]

I'm going to take a small risk and say no way this has anything to do with the high voltage or even the low voltages portion of the power supply.This problem is somewhere on the mains side input to the supply. Can you post the pictures you sent them? I am particularly interested in pictures of the back side of the power connector inside the machine and also the backside of the on/off switch and where the mains wires are attached to the power supply. A problem of this magnitude should take 5-10 minutes tops to nail down as to what is wrong. Watch out for ebay's time limit on returns and remember you have to pay return shipping and you won't get the good deal they get. Probably a lot cheaper to repair it. It does not sound like you ran the ohmmeter tests as I originally described and if you did what were the results?

Edit: You mentioned a surge. Nope it was not a "surge" and not a "voltage problem". It was a short on your 220 line somewhere on the output side of the switch. Bad switch, wiring attached to the switch or between the switch and supply, bad input transformer on the supply. I think that covers it.

Still doing the tests you mentioned, but here are the pics i sent to supplier. I have untill 20th Jan to get it sorted then ebay step in, also supplier have to pay for returns as it states this on the listing for faulty items.

[Retroplayer]

Still doing the tests you mentioned, but here are the pics i sent to supplier. I have untill 20th Jan to get it sorted then ebay step in, also supplier have to pay for returns as it states this on the listing for faulty items.

Do you have a picture of the connections at the power supply? Specifically the AC connections? I noted that the wires at the switch are black and red, but at the AC inlet, they are red and yellow. On mine, the outlet is connected directly to that switch to cut both rails of the AC completely from the machine. Obviously there is some middle connection going on in your machine.

EDIT: Blew up the picture a little better and I can see the black wire on the AC inlet now. Still, a pic of the connections at the PS would be helpful.

[buddydog]

Ok here you go. If nothing is "blown" off the back of the lines connector in the pictures, what you appear to have is the yellow (ground) attached to one side of the line. The yellow should be connected to the upper center ground connection. The way that connecter works is the black lead on the left in the picture is directly connected to one side of the line and goes on to be switched by the "black" side of the switch. The other side line input comes in from the power cord through the connector and then travels "down" to the fuse via that exposed metal vertical strip on the right side of the connector in the picture Nothing gets connected to that strip!!. It looks like the yellow ground is or was connected to that. Definitely a direct short and didn't even make it through the fuse. Incidentally when wired correctly there would be no connection to that exposed metal strip and if you touch it it will shock you. Anyway after traveling "down" the strip it reenters the power connector where a fuse is plugged in and then it crosses through the fuse to the left side where the red wire is connected and from there goes through the other side of the switch on the "red" buss. Before I go one tell me if the yellow wire is or was connected to that strip?

edit: I blew the picture up and that yellow ground WAS attached to the upper part of the "metal strip" and was blown off (or at lest it appears that way). That was your bang and light. NOW what to do? Was the machine grounded in some other way besides the power cord? If so you are lucky and the machine itself was not involved in the carnage. BUT I compared my wiring to yours on the logic board and I am pretty sure that is wrong also but the color codes may just be messed up. This would be a separate After we clear your short we can discus that issue.

[Retroplayer]

I believe it is just the angle of the picture, Buddy. I didn't even see the black wire and it looked like the ground wire had no connection when I first looked at it. But just in case, here are some pics of how mine is wired to compare:



That exposed metal comes from one of the IEC terminals, brings it down to the fuse, and through the fuse to the black wire.

[odinsminiatures]

Ok here you go. If nothing is "blown" off the back of the lines connector in the pictures, what you appear to have is the yellow (ground) attached to one side of the line. The yellow should be connected to the upper center ground connection. The way that connecter works is the black lead on the left in the picture is directly connected to one side of the line and goes on to be switched by the "black" side of the switch. The other side line input comes in from the power cord through the connector and then travels "down" to the fuse via that exposed metal vertical strip on the right side of the connector in the picture Nothing gets connected to that strip!!. It looks like the yellow ground is or was connected to that. Definitely a direct short and didn't even make it through the fuse. Incidentally when wired correctly there would be no connection to that exposed metal strip and if you touch it it will shock you. Anyway after traveling "down" the strip it reenters the power connector where a fuse is plugged in and then it crosses through the fuse to the left side where the red wire is connected and from there goes through the other side of the switch on the "red" buss. Before I go one tell me if the yellow wire is or was connected to that strip?

edit: I blew the picture up and that yellow ground WAS attached to the upper part of the "metal strip" and was blown off (or at lest it appears that way). That was your bang and light. NOW what to do? Was the machine grounded in some other way besides the power cord? If so you are lucky and the machine itself was not involved in the carnage. BUT I compared my wiring to yours on the logic board and I am pretty sure that is wrong also but the color codes may just be messed up. This would be a separate After we clear your short we can discus that issue.

No the machine was earthed (grounded) through the power cord only and as it was also connected with an earth on the inside back casing it did not seem necessary to add another.
The yellow lead is still connected as you described to the upper center ground connection there does appear to be a scrape of wire/metal that has fallen from the metal strip, but all 3 wires are still connected securely.
Glen

[odinsminiatures]

From ebay: Power Supply:220V/50Hz

Is that the operating voltage of you country? If it is, I'd verify with the seller that you didn't get one set for 120v

Yes have verified this with seller they say it is 220 for UK supply
Glen

[odinsminiatures]

I believe it is just the angle of the picture, Buddy. I didn't even see the black wire and it looked like the ground wire had no connection when I first looked at it. But just in case, here are some pics of how mine is wired to compare:



That exposed metal comes from one of the IEC terminals, brings it down to the fuse, and through the fuse to the black wire.

Yes mine is wired the same and still secure, the bit of metal seems to be a bit of old solder that has fallen off the exposed metal.
Thank you for the picture.
Glen

[Retroplayer]

Yes mine is wired the same and still secure, the bit of metal seems to be a bit of old solder that has fallen off the exposed metal.
Thank you for the picture.
Glen

Were you able to check your fuse?

[odinsminiatures]

Were you able to check your fuse?

No i have not checked it yet. Wondering if i void the warranty if i take it apart to check?
Glen

[Retroplayer]

No i have not checked it yet. Wondering if i void the warranty if i take it apart to check?
Glen

The fuse? That's obviously a user serviceable part. You just push the tray out. I can't imagine that the seller would expect you to call them every time you blow a fuse.

But if you do and you find it blown open... as mentioned above, don't simply replace it and give it another go. Something bad caused it to blow in the first place. But if you have an open fuse and replace the power supply/etc... it still won't work until you replace it. So might as well check it.

[buddydog]

Ok I see it now.the black shrink tubing had it looking to me like the yellow wire was hanging in space. Please check your fuse next but don't replace it.

On your picture of your control board,the largest connector (on the right in the picture) I believe it should be hooked up thus:
Numbering right to left in the picture:
From the power supply to the control board connector:
1.Ground
2. 24 volts (3 wires, one from supply and two small ones to the limit switches)
3 no connection
4. 5 volts
5. "L" light
6. No connection.
If this is confusing note that both the power supply and the control board are marked with these values so just "match" them up no matter the color code.While researching this I discovered my unit uses a piece of the yellow wire for the 5 volt feed! The same color is used for ground elsewhere! Yours could easily be mixed up since in their ultimate wisdom they used all the same yellow wire for all your connections! Amazing!

[odinsminiatures]

Ok ive located the fuse and its blown, black patch inside the glass fuse, brocken wire and the silver end is completely off.
So what amp fuse is this supposed to be.
Checking the above wiring.
Glen

[odinsminiatures]

Ok I see it now.the black shrink tubing had it looking to me like the yellow wire was hanging in space. Please check your fuse next but don't replace it.

On your picture of your control board,the largest connector (on the right in the picture) I believe it should be hooked up thus:
Numbering right to left in the picture:
From the power supply to the control board connector:
1.Ground
2. 24 volts (3 wires, one from supply and two small ones to the limit switches)
3 no connection
4. 5 volts
5. "L" light
6. No connection.
If this is confusing note that both the power supply and the control board are marked with these values so just "match" them up no matter the color code.While researching this I discovered my unit uses a piece of the yellow wire for the 5 volt feed! The same color is used for ground elsewhere! Yours could easily be mixed up since in their ultimate wisdom they used all the same yellow wire for all your connections! Amazing!

I've traced the wires as explained and they all go to the right places from control board to power supply.

[odinsminiatures]

The fuse? That's obviously a user serviceable part. You just push the tray out. I can't imagine that the seller would expect you to call them every time you blow a fuse.

But if you do and you find it blown open... as mentioned above, don't simply replace it and give it another go. Something bad caused it to blow in the first place. But if you have an open fuse and replace the power supply/etc... it still won't work until you replace it. So might as well check it.

I know it sounded stupid, but as im new to all this i did not know that there was a fuse located there, first thing i did was look for a fuse and could not find one and if it hadent have been for you guys helping me out and telling me where it was i would never have known where to find it...So thank you for that information, and yes the fuse is definitely blown.
Glen

[Retroplayer]

Well, if your wiring checks out, fuse is blown, then all that is left is a faulty power supply. If the tube had blown, it probably wouldn't have blown your circuit breaker and it would be very visible. Same for the 24V components.

If it had been the high voltage circuit, you would see arc burns for sure.

Your circuit breaker popping indicates to me, some type of short on the AC side of things which means most of your components should be ok.

As I mentioned, I would look for loose screws and nuts that may have found their way into the power supply. I wouldn't be surprised if you find something and your power supply is probably fine as well.

Regardless of what the seller does to remedy the situation (and I'm sure a remedy will only be sending you replacement parts to install yourself with shoddy instructions on how to do it) you are going to be getting your hands dirty here to get this going again. Perosnally, I would start with some continuity checks starting at the ac input and following it to the supply. On your supply you should have a connector on the left labeled L- FG AC AC. The two ACs are the live and neutral from your inlet. L- and FG are earth grounds which will connect to that yellow wire on your inlet and also to the chassis banana jack.

Do a continuity check between AC and AC pins, then each AC input and the L- and FG pins.

[odinsminiatures]

Well, if your wiring checks out, fuse is blown, then all that is left is a faulty power supply. If the tube had blown, it probably wouldn't have blown your circuit breaker and it would be very visible. Same for the 24V components.

If it had been the high voltage circuit, you would see arc burns for sure.

Your circuit breaker popping indicates to me, some type of short on the AC side of things which means most of your components should be ok.

As I mentioned, I would look for loose screws and nuts that may have found their way into the power supply. I wouldn't be surprised if you find something and your power supply is probably fine as well.

Regardless of what the seller does to remedy the situation (and I'm sure a remedy will only be sending you replacement parts to install yourself with shoddy instructions on how to do it) you are going to be getting your hands dirty here to get this going again. Perosnally, I would start with some continuity checks starting at the ac input and following it to the supply. On your supply you should have a connector on the left labeled L- FG AC AC. The two ACs are the live and neutral from your inlet. L- and FG are earth grounds which will connect to that yellow wire on your inlet and also to the chassis banana jack.

Do a continuity check between AC and AC pins, then each AC input and the L- and FG pins.

ok
done all the above, checked the power supply etc no loose parts or screws etc.
No evidence of any burn out or arcing anywhere in the machine, tube all looks intact too only thing i can find is the blown fuse but no obvious reason for it at all.
Glen

[odinsminiatures]

Well, if your wiring checks out, fuse is blown, then all that is left is a faulty power supply. If the tube had blown, it probably wouldn't have blown your circuit breaker and it would be very visible. Same for the 24V components.

If it had been the high voltage circuit, you would see arc burns for sure.

Your circuit breaker popping indicates to me, some type of short on the AC side of things which means most of your components should be ok.

As I mentioned, I would look for loose screws and nuts that may have found their way into the power supply. I wouldn't be surprised if you find something and your power supply is probably fine as well.

Regardless of what the seller does to remedy the situation (and I'm sure a remedy will only be sending you replacement parts to install yourself with shoddy instructions on how to do it) you are going to be getting your hands dirty here to get this going again. Perosnally, I would start with some continuity checks starting at the ac input and following it to the supply. On your supply you should have a connector on the left labeled L- FG AC AC. The two ACs are the live and neutral from your inlet. L- and FG are earth grounds which will connect to that yellow wire on your inlet and also to the chassis banana jack.

Do a continuity check between AC and AC pins, then each AC input and the L- and FG pins.

for safety reasons what amp should the fuse be? i replace the old one with.
Glen