Thread: Oh crap.........

Originally Posted by Big Shed

Mark, your lathe should still be under warranty?

If you read my link to xr6t's experience with Asset Machinery, you would be better off contacting them first before you do anything yourself.

Just my 2c but it could save you a lot hassle (and $$$$$)

I paid for the lathe on 24/12/09 and got receipt for freight dated 14/01/10
I cant find any thing about the warranty , so am guessing that it is 12months.

I read xr6t's comments in the link you posted, being circuit board challenged I am trying to find out as much as I can so when they ask questions I might know what they are talking about.

I sent Asset an email last night and phoned them this morning, the service bloke not there, so have to ring Monday morning.

Wonder what happen to xr6t ?

I would push the warranty on it, as it might be a common problem with them.
My earlier comment about a micro switch was based on me thinking you had a 12 x 36 lathe.

Dave

Looking at the pics, I would hazard a guess that at least three of the black boxes are shot. This is based on the presence of dark 'grot' like soot on the leads of the devices and on the circuit board below these devices. Likely causes, overvoltage on input, or severe overcurrent due to a major motor failure.

When I did electronic engineering 30+ years ago, one of the lecturers was often heard proclaiming that semiconductors were intended to protect fuses. Unfortunately this is still true.

I would be seeking warranty options at this point, as it is quite likely that the motor and the control module will need replacing. No point in replacing one at a time as if the other also has a fault, it will take out the replacement part in short order.

Following on from malb's comments, I believe the "black boxes" are MOSFETs, have read a few posts about these on various sites about the 7x mini lathes. They appear prone to failure.

If it is indeed a faulty motor that caused this failure, and if warranty replacement is not on the cards, then it is going to be a fairly expensive fix.

I have a backup solution waiting just for this eventuality, I acquired a 1hp 3phase motor and 1hp VFD when I bought my 2 axis DRO on Ebay. Have fitted the DRO and put the 3ph motor and VFD aside for a "rainy" day.

You could consider buying a suitable 1hp 3ph motor on Ebay as well as a VFD. These VFDs are now getting quite cheap, as are used 3ph motors.

Here is an example of a 2hp VFD

VARIABLE FREQUENCY DRIVE INVERTER VFD NEW 2HP 1.5KW 7A (eBay item 180515678895 end time 28-Feb-11 04:12:25 AEDST) : Business Industrial

1hp models can be had even cheaper.

Hi wm460,

Actually those "black boxes" are not mosfets, they are SCR's S6025L ( 25A 600V ) not hard to find, probably cost $2-3 each. You can usually replace them with equivalents or higher rated parts. The problem is (as Malb has already mentioned) what else has been fried in the process.

If you are lucky it might be just a case of replace the SCR's and you are up and running for a total cost of $20.or so.. if you are unlucky then it might be replacement motor AND control board.

Is there anyone in Tennant Creek that does electronic repairs, maybe a TV repair or better yet someone who does industrial electronics?

Regards
Ray
PS. The S6025L is the only one I can see a number on, it's possible some of the other "black boxes" might be different. The two legged ones might be diacs? hard to tell without seeing a bit more clearly...

Originally Posted by Big Shed

Here is an example of a 2hp VFD

VARIABLE FREQUENCY DRIVE INVERTER VFD NEW 2HP 1.5KW 7A (eBay item 180515678895 end time 28-Feb-11 04:12:25 AEDST) : Business Industrial

1hp models can be had even cheaper.

I wish you hadn't posted that. I bought my 2.2kw VFD from that very seller, but its price now is almost half what it was when I purchased 6 months ago!

I guess on the plus side, it gives me just a little extra budget for a lathe!

Yep some smoke has definitely escaped from that terminal one of the wires coming from it to the board looks cooked for sure.

My motor is an imperial one despite being manufactured in Taiwan ,circa 1979.
Cant find a motor anywhere near the dimensions for my mill ,all the new metric motors have short shafts around 48 -50mm , the shaft on my motor is closer to 80mm .
So when I get a determination on the fault ,and if it's the start windings I will be looking at a re-wind at the worst .

Just one thing on the list of electrical things that have died in the last few months around here .

Kev.

Yes I am hoping as it is just out of warranty they will come to the party.

Fred, Why 1hp 3ph motor not a single phase?

Ray, Nearest industrial electronics would be in Alice 500km away.

Originally Posted by Woodlee

Just one thing on the list of electrical things that have died in the last few months around here .

Kev.

Hope it is not something contagious going around.
If you find some one that rewind motor let me know please.

I believe there is a motor re-winder in Darwin , Im about to find out soon enough when I get the diag on my fizzer motor .
If not it will be Adelaide, more than likely Royce Cross .
Unless I can drag my Mother in laws' friend out of retirement.

Kev.

Originally Posted by wm460

Yes I am hoping as it is just out of warranty they will come to the party.

Fred, Why 1hp 3ph motor not a single phase?

Ray, Nearest industrial electronics would be in Alice 500km away.



Hope it is not something contagious going around.
If you find some one that rewind motor let me know please.

Mark, the 1hp 3ph came with the DRO and VFD as a package. It provides variable speed and fwd/rev via the VFD. VFDs don't work on single phase motors.

The system has lots of other very interesting features, I bought it on Ebay from the designer.

I have only installed the DRO readout and glass scales and haven't needed the VFD and motor at this stage, but it is there as a backup.

I had actually planned to use the VFD and motor on a wood lathe, but as I finished up buying an EVS wood lathe that didn't eventuate either.

How is the fix to your 920V coming along?

Been a bit busy around this week
Rang Asset Mon morning spoke to the service bloke and explained the problems then sent him the photos and he emailed back.

His reply.
Hi,

As the warranty for this machine is 12 months from the day of delivery, unfortunately the lathe is out of warranty, I suggest you get a local sparky to come and look at it, our service technicians are available for technical support if required, please let us know if you need further assistance, thanks.

My reply
Hi Andrew,

The delivery docket said it 2 weeks out of warranty

Regards,
Mark.

His reply
Hi,

I spoke with our spare parts department and we only have the complete circuit board in stock, so I spoke to my manager and he said to send the complete circuit board, I will post one to you asap, any problems please let me know, thanks.


Now I just have to be patient and wait for it to arrive.

I take it was for free under warranty? If so, good on them for looking after their customers.

Dave

Originally Posted by Woodlee

Yep some smoke has definitely escaped from that terminal one of the wires coming from it to the board looks cooked for sure.

lol...yep he definitely let too much out


and the pcb does look burnt also...meaning its probably not economically repairable

Hi Mark,

Well done, and full marks to Asset for backing their warantee, that's the sort of support you like to see.

I'm always of the view, that it's not what you do when things are going well that counts, it what you do when things go wrong.

Only concern I would have now, is if there is another fault (perhaps motor or wiring) that caused the control board failure. Keep your fingers crossed when you swap control boards over..

Regards
Ray