Author Topic: EEVblog #1160 - Weller Responds  (Read 51082 times)

0 Members and 1 Guest are viewing this topic.

Online EEVblog

  • Administrator
  • *****
  • Posts: 29491
  • Country: au
    • EEVblog
Re: EEVblog #1160 - Weller Responds
« Reply #625 on: January 03, 2019, 01:55:54 am »
You can see primary current skyrockets from 0.25A at 120VAC, the up to 4A at 190VAC. To 240VAC... I did not release the magic smoke. So a fuse would cover long-term primary overvoltage, a thermal fuse as well with that much heat dissipated in the primary it's heating up.

In this case of 240V on a 120V transformer, a primary fuse would blow almost instantly.
 

Offline IanB

  • Super Contributor
  • ***
  • Posts: 9514
  • Country: us
Re: EEVblog #1160 - Weller Responds
« Reply #626 on: January 03, 2019, 01:56:38 am »
... Could someone do an actual experiment to test the assumption that a fuse would help? ...

Measured a 120VAC transformer to 190VAC with no load. Past 150VAC it gets very loud.
It is an older Hammond (pre-china) 167M25 rated 25.2VAC 3A 75VA, similar in power to the Weller part but a more conservative build. Primary is 4R 0.77H and secondary 0.3R 50mH.

True input power is about 5W 115VAC going to 90W at 190VAC. Effective turns-ratio did not sag as I expected. I got 42VAC out at 190VAC in, I thought it would eventually clip.

You can see primary current skyrockets from 0.25A at 120VAC, the up to 4A at 190VAC. To 240VAC... I did not release the magic smoke. So a fuse would cover long-term primary overvoltage, a thermal fuse as well with that much heat dissipated in the primary it's heating up.

OK, that's cool. So at the rated load of 75 VA the primary current would be about 700 mA. Meaning a 3 A slow blow fuse should be OK for normal loads and turn on current. But the same 3 A fuse should blow rapidly at 240 V. Meaning such a fuse would be a good way of protecting the transformer from damage.
I'm not an EE--what am I doing here?
 

Online Wolfgang

  • Super Contributor
  • ***
  • Posts: 1138
  • Country: de
  • Its great if it finally works !
    • Electronic Projects for Fun
Re: EEVblog #1160 - Weller Responds
« Reply #627 on: January 03, 2019, 01:59:55 am »
No. Its *your* turn to prove that Wellers decision was not silly. The audience is waiting ...
Thanks for cutting to the chase. It's actually exactly the other way around. The claim is that Weller is doing something incredibly silly or reckless or dangerous. We're get to be presented with any solid evidence for this claim, even though it's reportedly glaringly obvious. Please do so. The audience is waiting. Note that "others do it differently" isn't enough.



Gents, its a bit late now in good old Europe, so I'll sum up for today.

I disagree that it is the job of consumers to prove that a product is unsafe. I will *never* buy from a company that asks for that. I buy from companies that I trust (see equipment list in my profile). Trust means that if customers has a concern, they will explain what they did and why it is OK. If they have done something wrong or maybe even just risky or unprofessionally, they will admit it and fix it without waffling discussions. In the Weller case I consider this an engineering blunder, a marketing catastrophy and an example of how not not handle customer concerns.

IMHO, everyone is free to decide on the cirteria he has chosen. Mine are the ones above. A weller for me ? Not even with a fuse now.

Have fun, but play safe. Never leave your soldering iron unattended.  >:D
  Wolfgang

 

Online timelessbeing

  • Frequent Contributor
  • **
  • Posts: 782
  • Country: 00
Re: EEVblog #1160 - Weller Responds
« Reply #628 on: January 03, 2019, 02:01:18 am »
Measured a 120VAC transformer to 190VAC with no load. Past 150VAC it gets very loud.
You should connect a load to it.
 

Online Brumby

  • Supporter
  • ****
  • Posts: 9143
  • Country: au
Re: EEVblog #1160 - Weller Responds
« Reply #629 on: January 03, 2019, 02:04:27 am »
You can see primary current skyrockets from 0.25A at 120VAC, the up to 4A at 190VAC. To 240VAC... I did not release the magic smoke. So a fuse would cover long-term primary overvoltage, a thermal fuse as well with that much heat dissipated in the primary it's heating up.

In this case of 240V on a 120V transformer, a primary fuse would blow almost instantly.

Yeah - This is something I felt was painfully obvious from the get-go.

This, together with Dave's clear acceptance of culpability in feeding 240V to the unit says to me we DON'T need to continue with any further references to the 240V user error.  This is not a fair scenario to dump on Weller.


The question of a fuse should be constrained to the usage of the unit at 110V.That is a fair scenario to dump on Weller - nothing else.

JMHO
 

Offline chris_leyson

  • Super Contributor
  • ***
  • Posts: 1289
  • Country: wales
Re: EEVblog #1160 - Weller Responds
« Reply #630 on: January 03, 2019, 02:15:03 am »
@floobydust. Thanks mate, at least you bothered to make a measurement  :-+ Respect
 

Offline Mr. Scram

  • Super Contributor
  • ***
  • Posts: 7721
  • Country: 00
  • Display aficionado
Re: EEVblog #1160 - Weller Responds
« Reply #631 on: January 03, 2019, 02:18:33 am »
No need for "others do it differently. Weller themselves do it differently!
I don't think many are saying it's dangerous as such, it's clearly not as they countless things don't have mains fuses, and the standard (in this case) do not require it.
But it is demonstrably silly - how so? Not only two videos of mine along with 25 pages of responses on what a silly decision it is, and the equally silly public response, but also the fact that most of Weller's other products have a fuse. Most products of Weller's having a safety feature and then a couple of them that deliberately don't is, well, silly. Especially when they refuse to explain why.
Some here seem to suggest not having a fuse is equivalent to Weller setting fire to your house or some such sensationalist claims. As you say, a fuse not required by law or regulation and many things don't come with fuses. That already nuances the discussion quite a bit. Beyond that point you'll have to forgive me my ignorance. The two videos and 25 pages have repeated numerous times that's it's silly to do this, but I don't seem to have really seen a solid explanation why. The most prevalent reasoning seems to be "industry standard", which sounds a lot like "you must because you must" and preserving the status quo for the sake of it. And sure it's not an expensive part, but that's not a demonstrable benefit in itself. Apparently the US and EU versions are different in that one us fused and the other isn't, which to me suggests there has been a concious decision there. I'd love to know more about that, but I doubt Weller is going to pop in and elaborate.
 

Offline IanB

  • Super Contributor
  • ***
  • Posts: 9514
  • Country: us
Re: EEVblog #1160 - Weller Responds
« Reply #632 on: January 03, 2019, 02:42:05 am »
This, together with Dave's clear acceptance of culpability in feeding 240V to the unit says to me we DON'T need to continue with any further references to the 240V user error.  This is not a fair scenario to dump on Weller.

The question of a fuse should be constrained to the usage of the unit at 110V.That is a fair scenario to dump on Weller - nothing else.

I don't really agree with that.

In this case of 240V on a 120V transformer, a primary fuse would blow almost instantly.

For me the question has always been about protecting my device from unnecessary damage. If I do what Dave did and accidentally plug the solder station into the wrong voltage, then without a fuse it will damage the unit beyond repair (I can't trust the transformer after it has started smoking). If there is a fuse and it blows instantly, then the unit may survive my mistake and continue to work.

I would rather not have to replace the soldering station if it can be avoided.
I'm not an EE--what am I doing here?
 

Offline Electro Detective

  • Super Contributor
  • ***
  • Posts: 2059
  • Country: au
Re: EEVblog #1160 - Weller Responds
« Reply #633 on: January 03, 2019, 03:08:21 am »
DJ's souved and dissected Weller carcass should be retrieved from the ---Bin Of Unfused Shame--- and reassembled with a suitable 120/120 CT to 24 volt isolation transformer

($35 to $60 depending on VA requirements  > any decent cheapie tranny should be better enameled than the honey coatings on the crusty deceased one,
and come stock with a thermal fuse fitted with a  -MUST- recommendation to use a primary fuse and the value. Reference: Altronics and Jaycar catalogues)

kit it out with a cheap glass fuse,

wired/connected for 120 volt operation

then plugged into 240 volts and see what happens   :popcorn:


Then swap out the zapped fuse and connect 120 x 2 for 240v, and see if it still works

All proceeding posted on Youtube of course   :clap:

with optional Grande Finale plugged into 440 volts (2 active legs/single phase) with a very temporary 3 phase plug to GPO socket death adapter   :scared: 

I'm betting a properly rated fuse will pop faster, perhaps crack or shatter, and the unit will survive unscathed and back to work
 

« Last Edit: January 03, 2019, 09:04:20 am by Electro Detective »
 
The following users thanked this post: SeanB

Offline bitwelder

  • Frequent Contributor
  • **
  • Posts: 807
  • Country: fi
Re: EEVblog #1160 - Weller Responds
« Reply #634 on: January 03, 2019, 07:46:33 am »
Measured a 120VAC transformer to 190VAC with no load.
Thanks for the experiment.

Just for completeness, 190VAC at 50 or 60 Hz ?
 

Online Fungus

  • Super Contributor
  • ***
  • Posts: 9899
  • Country: 00
Re: EEVblog #1160 - Weller Responds
« Reply #635 on: January 03, 2019, 09:59:04 am »
Are you intentionally ignoring the obvious? How often does one plugin appliances into the wrong voltage?

How often do people crash cars? Are all those annoying harnesses and expensive safety devices really necessary?
 

Offline Mr. Scram

  • Super Contributor
  • ***
  • Posts: 7721
  • Country: 00
  • Display aficionado
Re: EEVblog #1160 - Weller Responds
« Reply #636 on: January 03, 2019, 10:08:28 am »
How often do people crash cars? Are all those annoying harnesses and expensive safety devices really necessary?
How often do people crash cars into objects across the ocean? All we've seen here so far are very specific and fairly exceptional scenarios.
 

Online EEVblog

  • Administrator
  • *****
  • Posts: 29491
  • Country: au
    • EEVblog
Re: EEVblog #1160 - Weller Responds
« Reply #637 on: January 03, 2019, 11:20:47 am »
How often do people crash cars? Are all those annoying harnesses and expensive safety devices really necessary?
How often do people crash cars into objects across the ocean? All we've seen here so far are very specific and fairly exceptional scenarios.

This thread is long enough, there is no need for a car safety tangent please.
 
The following users thanked this post: Kean, Fungus

Offline Kean

  • Supporter
  • ****
  • Posts: 882
  • Country: au
  • Embedded systems & IT consultant
    • Kean Electronics
Re: EEVblog #1160 - Weller Responds
« Reply #638 on: January 03, 2019, 11:54:46 am »
Weller decided to save on safety features

I think something was lost in the translation from Swedish. Let me correct your English for you.

This model doesn't include a particular feature that protects the iron from gross mis-use such as supplying twice the intended voltage.

Please don't intentionally misattribute quotes to people.   :--
 

Online Fungus

  • Super Contributor
  • ***
  • Posts: 9899
  • Country: 00
Re: EEVblog #1160 - Weller Responds
« Reply #639 on: January 03, 2019, 12:25:48 pm »
All we've seen here so far are very specific and fairly exceptional scenarios.

Scenarios that really happen.

(but this has already been pointed out a zillion times in this thread, you're just refusing to accept it).

Mitigation costs a few cents, there's no excuse on a device that costs over $100 that gets sold to engineers.

(and this has also been pointed out a zillion times, you're just refusing to accept it).

Flipped around: What valid excuse does Weller have for doing this when all common sense and engineering practice says it's a bad idea? How would anybody justify Weller not adding a fuse? Spell it out for us...

 
The following users thanked this post: Kean, Richard Crowley, TheDane

Offline Mr. Scram

  • Super Contributor
  • ***
  • Posts: 7721
  • Country: 00
  • Display aficionado
Re: EEVblog #1160 - Weller Responds
« Reply #640 on: January 03, 2019, 01:19:12 pm »
Scenarios that really happen.

(but this has already been pointed out a zillion times in this thread, you're just refusing to accept it).

Mitigation costs a few cents, there's no excuse on a device that costs over $100 that gets sold to engineers.

(and this has also been pointed out a zillion times, you're just refusing to accept it).

Flipped around: What valid excuse does Weller have for doing this when all common sense and engineering practice says it's a bad idea? How would anybody justify Weller not adding a fuse? Spell it out for us...
I don't know why people are liking your post, because nobody here is denying that they have happened. Let's not pretend that anyone here does. I'm just asking how often it does happen and whether that's enough to justify it. As far as I'm aware, nobody has been able to answer that in a meaningful way. How can you say it's necessary or justified if you can't quantify anything? Engineers should be the last people to indulge in measures for the sake of them.

Somehow there seems to be a communications breakdown. It shouldn't be that hard to quantify something which is reportedly glaringly obviously necessary, even though it's not required by law and not found in many devices, yet instead we get "common sense" and "industry standard" and other truisms. Not accepting a mantra is not arguing in favour of removing the fuse or defending Weller. It'd be good if people wouldn't pretend it is. If the size of the problem is demonstrated, it all becomes a lot more substantial.
« Last Edit: January 03, 2019, 01:29:41 pm by Mr. Scram »
 
The following users thanked this post: timelessbeing

Offline glarsson

  • Frequent Contributor
  • **
  • Posts: 807
  • Country: se
Re: EEVblog #1160 - Weller Responds
« Reply #641 on: January 03, 2019, 01:26:00 pm »
Weller decided to save on safety features

I think something was lost in the translation from Swedish. Let me correct your English for you.

This model doesn't include a particular feature that protects the iron from gross mis-use such as supplying twice the intended voltage.
You surely act like someone working as a Weller spin doctor. Furthermore, you are acting childish and dishonest when you fake quotes. I did not write anything of what you attributed to me.
There are other ways a 120V appliance can see overvoltage.
« Last Edit: January 03, 2019, 01:49:30 pm by glarsson »
 
The following users thanked this post: Electro Detective

Online Fungus

  • Super Contributor
  • ***
  • Posts: 9899
  • Country: 00
Re: EEVblog #1160 - Weller Responds
« Reply #642 on: January 03, 2019, 02:08:01 pm »
I'm just asking how often it does happen and whether that's enough to justify it.

There's obviously not enough data for that, but there's been (I believe) three reports of it happening just in this thread.

If it's often enough to happen a widely followed blogger? That's when Weller should have had enough sense to admit they're Doing It Wrong.

They failed.

Completely.
 

Offline Mr. Scram

  • Super Contributor
  • ***
  • Posts: 7721
  • Country: 00
  • Display aficionado
Re: EEVblog #1160 - Weller Responds
« Reply #643 on: January 03, 2019, 02:40:02 pm »
There's obviously not enough data for that, but there's been (I believe) three reports of it happening just in this thread.

If it's often enough to happen a widely followed blogger? That's when Weller should have had enough sense to admit they're Doing It Wrong.

They failed.

Completely.
I think we can agree there's not enough data. Three cases with fairly exceptional circumstances on a forum filled with people doing unusual things with electronics doesn't sound like a very high rate. The fact that Dave is widely followed doesn't make for a more statistically significant incident, just a more publicised one. It's not a lot to go on if a company is going to be vehemently crucified. Again, I'd prefer Weller to make an actual statement about their deliberations but I doubt that's going to happen.
 

Offline drussell

  • Super Contributor
  • ***
  • Posts: 1049
  • Country: ca
  • Hardcore Geek
Re: EEVblog #1160 - Weller Responds
« Reply #644 on: January 03, 2019, 03:32:34 pm »
That's when Weller should have had enough sense to admit they're Doing It Wrong.



Sorry, couldn't resist...  :)

Quote
They failed.

Completely.

Hyperbole much?   ;)
 

Online Fungus

  • Super Contributor
  • ***
  • Posts: 9899
  • Country: 00
Re: EEVblog #1160 - Weller Responds
« Reply #645 on: January 03, 2019, 04:07:28 pm »
I think we can agree there's not enough data. Three cases with fairly exceptional circumstances on a forum filled with people doing unusual things with electronics doesn't sound like a very high rate.

Does it have to be "very high" before you take any action?
 

Offline Mr. Scram

  • Super Contributor
  • ***
  • Posts: 7721
  • Country: 00
  • Display aficionado
Re: EEVblog #1160 - Weller Responds
« Reply #646 on: January 03, 2019, 04:21:05 pm »
Does it have to be "very high" before you take any action?
The counter question would be whether you take action when the impact may very well be marginal or nearly non-existent. Protecting against everything isn't possible, so the sensible approach is to ascertain what failure modes have the biggest impact and to protect against those.
 

Online Fungus

  • Super Contributor
  • ***
  • Posts: 9899
  • Country: 00
Re: EEVblog #1160 - Weller Responds
« Reply #647 on: January 03, 2019, 04:27:34 pm »
Does it have to be "very high" before you take any action?
The counter question would be whether you take action when the impact may very well be marginal or nearly non-existent. Protecting against everything isn't possible, so the sensible approach is to ascertain what failure modes have the biggest impact and to protect against those.

"Impact" includes damage to your company reputation as well as damage that may be caused by your products.

A reputable company would at least do the things that:
a) Are very cheap to do
b) Their competitors are doing
c) The target demographic is very likely to notice
 

Offline Mr. Scram

  • Super Contributor
  • ***
  • Posts: 7721
  • Country: 00
  • Display aficionado
Re: EEVblog #1160 - Weller Responds
« Reply #648 on: January 03, 2019, 04:53:42 pm »
"Impact" includes damage to your company reputation as well as damage that may be caused by your products.

A reputable company would at least do the things that:
a) Are very cheap to do
b) Their competitors are doing
c) The target demographic is very likely to notice
It being cheap is obviously no reason in itself. Not to mention it's not actually that cheap in a world where tenths of cents count. We've discussed before how the status quo and truisms are no actual reasons either. The last argument essentially is "because we're making it into an issue". First making a fuss and then pointing at damage supposedly caused by that fuss as a reason to act is inventing an argument. It could even be mistaken for the "I choose to be outraged by something, so you must act" fallacy which seems popular at the moment. It doesn't eliminate the burden of proof. You'll still need to address whether that fuss is valid, which has so far been proven to be rather tricky.
« Last Edit: January 03, 2019, 04:56:25 pm by Mr. Scram »
 

Online Fungus

  • Super Contributor
  • ***
  • Posts: 9899
  • Country: 00
Re: EEVblog #1160 - Weller Responds
« Reply #649 on: January 03, 2019, 04:55:25 pm »
You'll still need to address whether that fuss is valid, which has so far been proven to be rather tricky.

a) Doesn't sound like you're trying to build a company, only count beans.
b) What's your opinion of this:

https://www.eevblog.com/forum/contests/win-a-weller/

 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf