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Crappy mains adapters & crappy designs

N

Nico Coesel

Jan 1, 1970
0
I feel like ranting and I think it is on-topic so here it goes:

One of the things I start to hate more and more is when potentially
nice equipment fails because it wasn't designed to deal with something
trivial like a mains adapter dying.

Currently I have 4 dead wireless access points (from a very
respectable firm, not some cheap-ass shit) dead on the bench here. All
because their mains adapters died.

I posted a picture of a disassembled adapter here:
http://selvi.nctdev.nl/adapter.jpg

Notice the burn marks on the rubber foam which was placed between the
casing and the solder side of the PCB.

I suspect the adapters started to provide DC pulses which somehow
partly erased the flash memories in the wireless access points.
 
J

John Larkin

Jan 1, 1970
0
I feel like ranting and I think it is on-topic so here it goes:

One of the things I start to hate more and more is when potentially
nice equipment fails because it wasn't designed to deal with something
trivial like a mains adapter dying.

Currently I have 4 dead wireless access points (from a very
respectable firm, not some cheap-ass shit) dead on the bench here. All
because their mains adapters died.

I posted a picture of a disassembled adapter here:
http://selvi.nctdev.nl/adapter.jpg

Notice the burn marks on the rubber foam which was placed between the
casing and the solder side of the PCB.

I suspect the adapters started to provide DC pulses which somehow
partly erased the flash memories in the wireless access points.

We sell a few little boxes that are powered from a 12-volt wart. We
always start with a polyfuse, followed by a 15 volt transzorb, which
also gives reverse polarity protection.

John
 
H

Homer J Simpson

Jan 1, 1970
0
Currently I have 4 dead wireless access points (from a very
respectable firm, not some cheap-ass shit) dead on the bench here. All
because their mains adapters died.

I posted a picture of a disassembled adapter here:
http://selvi.nctdev.nl/adapter.jpg

Looking at these I suspect they are using a series cap to reduce the voltage
to the transformer.

The WAPs no longer work with a good PS?
 
E

Ecnerwal

Jan 1, 1970
0
One of the things I start to hate more and more is when potentially
nice equipment fails because it wasn't designed to deal with something
trivial like a mains adapter dying.

More to the point, the equipment might be nice, but management decided
that a power supply was a commodity item to be sourced from China -
though I suspect your entire units were made there.

I have a very expensive, now very obsolete, US-made networking box that
does some esoteric processing which lets us run a segment of network
over a wire that would not otherwise run it. One day it stopped working.
I eventually figured out that the cheap-Chinese power supply had crapped
out (this was not overly obvious since the lights were still on, as it
was not dead on all 3 voltages).

I pulled an old clunky linear supply from the junkbox and spliced it
into the connector, even though the unit was still under warranty. If I
had gotten the warranty replacement, it would have been the same crappy
quality, and my tolerance for that is limited on boxes that cause much
crying out and gnashing of teeth when they break. I did inform the
company of what I had done, and why, but got no response from them.
 
J

Joerg

Jan 1, 1970
0
Nico said:
I feel like ranting and I think it is on-topic so here it goes:

One of the things I start to hate more and more is when potentially
nice equipment fails because it wasn't designed to deal with something
trivial like a mains adapter dying.

Currently I have 4 dead wireless access points (from a very
respectable firm, not some cheap-ass shit) dead on the bench here. All
because their mains adapters died.

I posted a picture of a disassembled adapter here:
http://selvi.nctdev.nl/adapter.jpg

Notice the burn marks on the rubber foam which was placed between the
casing and the solder side of the PCB.

I suspect the adapters started to provide DC pulses which somehow
partly erased the flash memories in the wireless access points.

With all due respect that does not look like stuff from a respectable
firm. There are wall warts from reputable sources such as Condor/Ault
but it seems this "respectable firm" might have cut a corner here and
saved a buck.

Check out SMC. I've got their Barricade router here and it has a
built-in switcher. Nothing gets hot, ever. It's totally cool to the
touch. Imagine, a built-in power supply. Wow. What a concept. Guess
people slowly figured out how grandpa's tube radios were designed and
why they last so long.

Oh, BTW, that Barricade router has a full metal enclosure. None of this
plastics stuff. Byu some real industry-grade gear and you shouldn't have
that problem. If it has a wall wart look for something better. If it has
a cheap wall wart, run.
 
J

jasen

Jan 1, 1970
0
Looking at these I suspect they are using a series cap to reduce the voltage
to the transformer.

what's the 400V electrolytic capacitor for then?

As I read it the small yellow box and the tranformer looking thing are a
capacitor across the input and a common-mode choke, the large yellow box
is the transformer
 
T

Terry Given

Jan 1, 1970
0
jasen said:
what's the 400V electrolytic capacitor for then?

As I read it the small yellow box and the tranformer looking thing are a
capacitor across the input and a common-mode choke, the large yellow box
is the transformer

yep.

I've pulled a fair few of these to bits. the construction ranges from
excellent to appalling.

The trick is to stick to a reputable manufacturer.

The problem is without a hacksaw, you cant see what they are like!

Meanwell make reasonably good stuff.

Cheers
Terry
 
W

Winfield Hill

Jan 1, 1970
0
I feel like ranting and I think it is on-topic so here it goes:

One of the things I start to hate more and more is when potentially
nice equipment fails because it wasn't designed to deal with something
trivial like a mains adapter dying.

Currently I have 4 dead wireless access points (from a very
respectable firm, not some cheap-ass shit) dead on the bench here. All
because their mains adapters died.

I posted a picture of a disassembled adapter here:http://selvi.nctdev.nl/adapter.jpg

Notice the burn marks on the rubber foam which was placed between the
casing and the solder side of the PCB.

I suspect the adapters started to provide DC pulses which somehow
partly erased the flash memories in the wireless access points.

How about doing us all a favor and naming names?
 
I feel like ranting and I think it is on-topic so here it goes:

One of the things I start to hate more and more is when potentially
nice equipment fails because it wasn't designed to deal with something
trivial like a mains adapter dying.

Currently I have 4 dead wireless access points (from a very
respectable firm, not some cheap-ass shit) dead on the bench here. All
because their mains adapters died.

I posted a picture of a disassembled adapter here:http://selvi.nctdev.nl/adapter.jpg

Notice the burn marks on the rubber foam which was placed between the
casing and the solder side of the PCB.

I suspect the adapters started to provide DC pulses which somehow
partly erased the flash memories in the wireless access points.

Not Cisco Systems (Linksys)?
I plug mine in a good quality powerstrip that has surge protection and
all the bells and whistles no problems so far...
 
M

mpm

Jan 1, 1970
0
Currently I have 4 dead wireless access points...

And it's only going to get worse with new government standards for
higher efficiency wall warts!
Unless of course, these same Standards weed out all the incompetent
designer wannabees.
But I doubt it.

I think the California law goes into effect this year??
-mpm
 
E

Eeyore

Jan 1, 1970
0
mpm said:
And it's only going to get worse with new government standards for
higher efficiency wall warts!

Bwahahahahahahhaha
 
N

Nico Coesel

Jan 1, 1970
0
Not Cisco Systems (Linksys)?

Well, in fact the 4 units are from Linksys placed in different
locations in a building on different mains groups (2 powered from a
UPS).
 
N

Nico Coesel

Jan 1, 1970
0
Homer J Simpson said:
Looking at these I suspect they are using a series cap to reduce the voltage
to the transformer.

The WAPs no longer work with a good PS?

I tried that, but no go.
 
H

Homer J Simpson

Jan 1, 1970
0
what's the 400V electrolytic capacitor for then?

As I read it the small yellow box and the tranformer looking thing are a
capacitor across the input and a common-mode choke, the large yellow box
is the transformer

It looks too small for 50/60 Hz unless it's an SMPS in which case it gives
me no confidence.
 
J

joseph2k

Jan 1, 1970
0
Joerg said:
With all due respect that does not look like stuff from a respectable
firm. There are wall warts from reputable sources such as Condor/Ault
but it seems this "respectable firm" might have cut a corner here and
saved a buck.

Check out SMC. I've got their Barricade router here and it has a
built-in switcher. Nothing gets hot, ever. It's totally cool to the
touch. Imagine, a built-in power supply. Wow. What a concept. Guess
people slowly figured out how grandpa's tube radios were designed and
why they last so long.

Oh, BTW, that Barricade router has a full metal enclosure. None of this
plastics stuff. Byu some real industry-grade gear and you shouldn't have
that problem. If it has a wall wart look for something better. If it has
a cheap wall wart, run.

Of course, if you know your mains are crappy, you should have upstream
protection for the wall warts.
 
J

joseph2k

Jan 1, 1970
0
Nico said:
Well, in fact the 4 units are from Linksys placed in different
locations in a building on different mains groups (2 powered from a
UPS).

That's a really crappy UPS that let something through that wasted something
dowqnstream.
 
J

Joerg

Jan 1, 1970
0
joseph2k said:
Nico Coesel wrote:




That's a really crappy UPS that let something through that wasted something
dowqnstream.

Or crappy power supplies that barely hung on and then collapsed. I have
seen some horrible "designs" where stuff had turned brown just from
normal operation. Others had 300V devices on directly rectified mains
and were marketed in Europe, meaning their ratings were exceeded even
under perfectly normal line conditions. Then there was one that got
freaking hot and the mfg said it was normal. One fine day the ambient
temp went a wee bit above 30C and ... POOF.
 
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