> On Sunday, October 17, 2021 at 5:08:18 PM UTC, Joerg wrote:
>> On 10/16/21 1:00 PM, Joerg wrote:
>>> With a lot of Sherlock Holmes sniffing I could find it but the
>>> schematics for those things are horrid.
>>>
>>> https://www.audio-thai.com/index.php?topic=15325.0
>>>
>>> I have the HY3030EX (30V/30A). The problem is that it shows arbitrarily
>>> high currents that aren't there and they are proportionate to the set
>>> voltage. Shows 11A at max voltage without any load. Of course, nothing
>>> becomes hot because those are fake numbers. Once it hits overcurrent it
>>> locks itself up and the output voltage drops to zero. Has to be
>>> power-cycled it every time.
>>>
>>> The internal connections appear to be ok.
>>>
>>> Maybe it ain't worth repairing but maybe one of you had that happen?
>>>
>> Gentlemen, found it. It wasn't just one poor solder joint but three. All
>> in the connection from the big current shunt to the 7107 display board
>> for the current display, plus one on the voltage display board. Not sure
>> how but this also caused the power supply to lock up.
>>
>> If someone else has that happen: Check the blue and black wires going
>> through a toroid towards the back of the unit. They measure sort of ok
>> but give them a tug near the solder joints and the resistance changes.
>>
>> I can't remember when I last saw such a poor solder job. Basically
>> consisting of splats and dull blobs. I'll have to take the whole thing
>> apart and resolder the wires. Considering that they also jammed in lots
>> of the screws because many things didn't line up that won't be fun.
>> --
>> Regards, Joerg
>>
>> http://www.analogconsultants.com/
>
> Glad you found it. (I mentioned that resistor first, since
> I always check high-power parts first; And, it seemed like the
> PS output was zero, with any load,)
>
It wasn't zero, you could set the voltage correctly until it locked up
with a fake overcurrent depending on potmeter settings. The solder
problems are in the cable path but also in the ground cable path of the
voltage display.
> ALWAYS first assume solder joints are a
> cause and re-solder anything remotely suspicious.
> In a mass-produced product, the solder-process QC
> is too easily 'relaxed'; and weak joints can be
> hard to detect.
>
You sure could call that soldering style "relaxed" :-)
> Actually when troubleshooting, there is a long list of basic
> steps. Here on sed, I tend to assume these were checked off.
>
Well, you can't always see it, only after I used the mirror from my
Bernstein set. I was hoping someone had experienced the same thing.
Meatime I found yet another bug, a ceramic capacitor is "touchy" and
makes the current display go crazy. So that also needs to be replaced.
> Would we benefit from a "s.e.d.-level" repair FAQ?
>
> regards, RS
>
> >
> > > watch the guy soldering at 23:01-23:05
> > >
> > > https://youtu.be/HF0E8WeEUVM?t=1381
> > >
> > ** Bloody heck !!!!
> >
> > That iron tip must be glowing red to go so fast, just look at the smoke coming off,
> > Terrible, crazy idea.
>
> if you are paid by how many you can make in a day it is a great idea ..
>
** Silly, false criterion.
That manager guy looks like he would be more at home running a brothel filled with 12 year old girls.
Maybe he does that too.
...... Phil
Reply by Lasse Langwadt Christensen●October 17, 20212021-10-17
søndag den 17. oktober 2021 kl. 22.48.18 UTC+2 skrev palli...@gmail.com:
> lang...@fonz.dk wrote:
> ===================
> > > -
> > watch the guy soldering at 23:01-23:05
> >
> > https://youtu.be/HF0E8WeEUVM?t=1381
> >
> ** Bloody heck !!!!
>
> That iron tip must be glowing red to go so fast, just look at the smoke coming off,
> Terrible, crazy idea.
if you are paid by how many you can make in a day it is a great idea ..
Reply by Rich S●October 17, 20212021-10-17
On Sunday, October 17, 2021 at 8:48:18 PM UTC, palli...@gmail.com wrote:
> lang...@fonz.dk wrote:
> ===================
> > > -
> > watch the guy soldering at 23:01-23:05
> >
> > https://youtu.be/HF0E8WeEUVM?t=1381
> >
> ** Bloody heck !!!!
>
> That iron tip must be glowing red to go so fast, just look at the smoke coming off,
> Terrible, crazy idea.
>
>
>
> ..... Phil
Aha - the detective Lasse, scores again. Thanks!
well said, Phil!
they are may get joints that Look ok, on the surface, but..
what darkness lurks beneath?
Soldering is a chemical and mechanical process.
You can speed up the chemical reaction with
higher temp, up to a point. (...Until
you degrade the flux, the PCB, etc.)
But the mechanical? there's that physical
thermal time constant of the assembly....
regards, RS
** Bloody heck !!!!
That iron tip must be glowing red to go so fast, just look at the smoke coming off,
Terrible, crazy idea.
..... Phil
Reply by Lasse Langwadt Christensen●October 17, 20212021-10-17
søndag den 17. oktober 2021 kl. 19.08.18 UTC+2 skrev Joerg:
> On 10/16/21 1:00 PM, Joerg wrote:
> > With a lot of Sherlock Holmes sniffing I could find it but the
> > schematics for those things are horrid.
> >
> > https://www.audio-thai.com/index.php?topic=15325.0
> >
> > I have the HY3030EX (30V/30A). The problem is that it shows arbitrarily
> > high currents that aren't there and they are proportionate to the set
> > voltage. Shows 11A at max voltage without any load. Of course, nothing
> > becomes hot because those are fake numbers. Once it hits overcurrent it
> > locks itself up and the output voltage drops to zero. Has to be
> > power-cycled it every time.
> >
> > The internal connections appear to be ok.
> >
> > Maybe it ain't worth repairing but maybe one of you had that happen?
> >
> Gentlemen, found it. It wasn't just one poor solder joint but three. All
> in the connection from the big current shunt to the 7107 display board
> for the current display, plus one on the voltage display board. Not sure
> how but this also caused the power supply to lock up.
>
> If someone else has that happen: Check the blue and black wires going
> through a toroid towards the back of the unit. They measure sort of ok
> but give them a tug near the solder joints and the resistance changes.
>
> I can't remember when I last saw such a poor solder job. Basically
> consisting of splats and dull blobs. I'll have to take the whole thing
> apart and resolder the wires. Considering that they also jammed in lots
> of the screws because many things didn't line up that won't be fun.
> --
On Sun, 17 Oct 2021 12:56:52 -0700 (PDT), Rich S
<richsulinengineer@gmail.com> wrote:
>On Sunday, October 17, 2021 at 5:08:18 PM UTC, Joerg wrote:
>> On 10/16/21 1:00 PM, Joerg wrote:
>> > With a lot of Sherlock Holmes sniffing I could find it but the
>> > schematics for those things are horrid.
>> >
>> > https://www.audio-thai.com/index.php?topic=15325.0
>> >
>> > I have the HY3030EX (30V/30A). The problem is that it shows arbitrarily
>> > high currents that aren't there and they are proportionate to the set
>> > voltage. Shows 11A at max voltage without any load. Of course, nothing
>> > becomes hot because those are fake numbers. Once it hits overcurrent it
>> > locks itself up and the output voltage drops to zero. Has to be
>> > power-cycled it every time.
>> >
>> > The internal connections appear to be ok.
>> >
>> > Maybe it ain't worth repairing but maybe one of you had that happen?
>> >
>> Gentlemen, found it. It wasn't just one poor solder joint but three. All
>> in the connection from the big current shunt to the 7107 display board
>> for the current display, plus one on the voltage display board. Not sure
>> how but this also caused the power supply to lock up.
>>
>> If someone else has that happen: Check the blue and black wires going
>> through a toroid towards the back of the unit. They measure sort of ok
>> but give them a tug near the solder joints and the resistance changes.
>>
>> I can't remember when I last saw such a poor solder job. Basically
>> consisting of splats and dull blobs. I'll have to take the whole thing
>> apart and resolder the wires. Considering that they also jammed in lots
>> of the screws because many things didn't line up that won't be fun.
>> --
>> Regards, Joerg
>>
>> http://www.analogconsultants.com/
>
>Glad you found it. (I mentioned that resistor first, since
>I always check high-power parts first; And, it seemed like the
>PS output was zero, with any load,)
>
>ALWAYS first assume solder joints are a
>cause and re-solder anything remotely suspicious.
>In a mass-produced product, the solder-process QC
>is too easily 'relaxed'; and weak joints can be
>hard to detect.
>
>Actually when troubleshooting, there is a long list of basic
>steps. Here on sed, I tend to assume these were checked off.
>
>Would we benefit from a "s.e.d.-level" repair FAQ?
>
>regards, RS
Even the Chinese can have a bad day once in a while.
Reply by Rich S●October 17, 20212021-10-17
On Sunday, October 17, 2021 at 5:08:18 PM UTC, Joerg wrote:
> On 10/16/21 1:00 PM, Joerg wrote:
> > With a lot of Sherlock Holmes sniffing I could find it but the
> > schematics for those things are horrid.
> >
> > https://www.audio-thai.com/index.php?topic=15325.0
> >
> > I have the HY3030EX (30V/30A). The problem is that it shows arbitrarily
> > high currents that aren't there and they are proportionate to the set
> > voltage. Shows 11A at max voltage without any load. Of course, nothing
> > becomes hot because those are fake numbers. Once it hits overcurrent it
> > locks itself up and the output voltage drops to zero. Has to be
> > power-cycled it every time.
> >
> > The internal connections appear to be ok.
> >
> > Maybe it ain't worth repairing but maybe one of you had that happen?
> >
> Gentlemen, found it. It wasn't just one poor solder joint but three. All
> in the connection from the big current shunt to the 7107 display board
> for the current display, plus one on the voltage display board. Not sure
> how but this also caused the power supply to lock up.
>
> If someone else has that happen: Check the blue and black wires going
> through a toroid towards the back of the unit. They measure sort of ok
> but give them a tug near the solder joints and the resistance changes.
>
> I can't remember when I last saw such a poor solder job. Basically
> consisting of splats and dull blobs. I'll have to take the whole thing
> apart and resolder the wires. Considering that they also jammed in lots
> of the screws because many things didn't line up that won't be fun.
> --
> Regards, Joerg
>
> http://www.analogconsultants.com/
Glad you found it. (I mentioned that resistor first, since
I always check high-power parts first; And, it seemed like the
PS output was zero, with any load,)
ALWAYS first assume solder joints are a
cause and re-solder anything remotely suspicious.
In a mass-produced product, the solder-process QC
is too easily 'relaxed'; and weak joints can be
hard to detect.
Actually when troubleshooting, there is a long list of basic
steps. Here on sed, I tend to assume these were checked off.
Would we benefit from a "s.e.d.-level" repair FAQ?
regards, RS
Reply by Joerg●October 17, 20212021-10-17
On 10/16/21 1:00 PM, Joerg wrote:
> With a lot of Sherlock Holmes sniffing I could find it but the
> schematics for those things are horrid.
>
> https://www.audio-thai.com/index.php?topic=15325.0
>
> I have the HY3030EX (30V/30A). The problem is that it shows arbitrarily
> high currents that aren't there and they are proportionate to the set
> voltage. Shows 11A at max voltage without any load. Of course, nothing
> becomes hot because those are fake numbers. Once it hits overcurrent it
> locks itself up and the output voltage drops to zero. Has to be
> power-cycled it every time.
>
> The internal connections appear to be ok.
>
> Maybe it ain't worth repairing but maybe one of you had that happen?
>
Gentlemen, found it. It wasn't just one poor solder joint but three. All
in the connection from the big current shunt to the 7107 display board
for the current display, plus one on the voltage display board. Not sure
how but this also caused the power supply to lock up.
If someone else has that happen: Check the blue and black wires going
through a toroid towards the back of the unit. They measure sort of ok
but give them a tug near the solder joints and the resistance changes.
I can't remember when I last saw such a poor solder job. Basically
consisting of splats and dull blobs. I'll have to take the whole thing
apart and resolder the wires. Considering that they also jammed in lots
of the screws because many things didn't line up that won't be fun.
--
Regards, Joerg
http://www.analogconsultants.com/
Reply by legg●October 17, 20212021-10-17
On Sat, 16 Oct 2021 15:32:46 -0700, Joerg <news@analogconsultants.com>
wrote:
>On 10/16/21 2:49 PM, legg wrote:
>> On Sat, 16 Oct 2021 13:00:19 -0700, Joerg <news@analogconsultants.com>
>> wrote:
>>
>>> HY3030EX
>>
>> Did you check out the A/D reference?
>>
>
>Looks ok. The main board is sending a voltage up to the ADC for the
>current display which varies with the set voltage (but shouldn't). The
>current signaling runs in the tens of millivolts which was a poor design
>decision and they had to add a CM toroid, probably to get that quiet.
In Schematic, it looks like current sensing is completely independent
-
A jellybean 7107 circuit. No controller influence.
Check isolated supply levels for this section.
RL