• Hello MLAers! We've re-enabled auto-approval for accounts. If you are still waiting on account approval, please check this thread for more information.

Quadra 700 Explodes: Magic Smoke event of epic proportions!

Trash80toHP_Mini

Trash80toHP_Mini

NIGHT STALKER
68040
GAAAHHHHH!!!!!!!!!!!!!!!!!! 8-o The apartment still reeks of it! I'm still amazed that it didn't quite set off the smoke alarm. If I hadn't been almost next to it when it audibly crackled banged and sizzled to unplug it, the smoke alarm would have certainly called me to it!

I hauled the bone stock Quadra 700 out from under the table for playtime last night and it booted up just fine, something funky was going on with the file system when I tried to move TattleTech onto it via Zip, but that wasn't the problem. So I shut it down, figuring I'd get back to it today. I left it plugged in and it just blew up about a half hour later! Haven't checked it out yet, but the soft power circuitry in the PSU is undoubtedly going to make for some very cool piccies tonight after work! [;)] ]'>

 
I didn't spot any flames, but the PSU was hot to the touch. I hope the quick pics I shot of on the old phone show the clouds of magic smoke. I wish I'd gotten one of the smoke filled case when I opened it up. :O

 
I put money on a switching transistor that started sticking and finally achieved the thermal race threshold.

 
my guess is the .23 µF HV caps went.

Fairly common.

I was fixing a IIgs PSU last night. an yesssssssssssssssss they REEK! and make tons of smoke :)

IMG_1716.JPG

 
Aren't the Quadra 700, 900 and 950 supposed to be one of the safer ones/with good caps? Or did I miss something? :-/

 
The Q700's Logic Board is pretty solid yes,

However a Power Supply issue, such as this, Can happen to any model.

 
YESSSSSSSSSSS!!!!!!!!!!!!!!!!!! She boots! [:D] ]'>

Came home from lunch and just had to try it, no problems at all using the PSU from the Quadra 7100.

Luckily, the Quadra 700/7600/G4/800 hack makes that spare Q700 PSU available for the replacement and I can use the charred remaoins of this case for the ATX hack. [;)] ]'>

Double redundant Q700 backup is a good thing! :approve:

It looks like I need to get out the Plastic Shoe Box of Power Center Goodness out and finally build the GFCI protected power strip for the workbench. Gotta check out the newfangled circuit breakers as well, they've got a hair trigger for failures like this.

I also have to remember to flip the main switch off when it's not playtime . . . :-/

 
( if you get a moment ) Pull the lid off that toasty PSU, shoot a picture of the PCB, so we can see what component snap/crackle/popped.

 
Yeppers. I'll try to get some pics up of the dearly departed PSU's giblets tonight. Meanwhile I've offloaded the Magic smoke pics off the Camera, I'll do those right after dinner . . .

. . . and maybe a little nap. |)

 
And, of corse if you wanted to throw a few dollars at it, I could fix that up for you. i am almost positive it was a HV cap explode.

 
The giblets I'll hold in reserve, the case will be the chassis for the ATX conversion. }:)

What are the odds of having EXACTLY the same parts detonate in two different PSUs? :?:

 
I'd back Uniserver's diagnosis, pending sighting of pics.

Also, I wouldn't rush to write off the rest of that machine. Those caps fail open, so no damaging electrical pulse goes forward. They usually only damage other components if the spilled oil and ruptured plastic actually flames enough to burn something adjacent. Chances are, that unit is reparable quite easily, though the soot and oil residue can look dramatic on first glance. I've recently had that experience with a printer and an oscilloscope, as well as in modular PSUs - all fixed.

Rick

 
Well, the old ENV-3 got something to show, but nothing like it was when up close & personal. 8-o

Q700explosion.0.2p.jpg

Q700explosion.1.2p.jpg

Of course, I did wait to take the photos until after I unplugged the thing and determined that I didn't need the fire extinguisher . . .

. . . taking pics was pretty much the last thing on my mind there for a bit. :-/

Maybe if the flash had gone off it would have lit the smoke against a darker background, dunno. Just figure there was like 10x as much smoke as it looks in the crappy phone-pix. :O

 
You must log in or register to reply here.
Back
Top