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Old 9th November 2011, 06:48 PM   #31
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Default Lost warranty on my hypex

I thought it would be just fair to be as critical with hypex as with connex and partially disassembled my unit.

First picture shows the area of the input rectifier.
There is an ugly isolation sleeve that which isolates the screw vs. the caps.
Ugly, but when measuring I found a creepage over the surface of >6mm.
and a thickness of the sleeve of 0.4mm-0.5mm.
The input rectifier itself has a washer of 0.5mm thickness and the plastic package of the rectifier is fully isolated. Wow, somebody did not trust on the thickness of the plastic package and added the washer.
Also the insulation bags of the Mosfets measure approx 0.5mm thickness.
Perfect fit to Jan Peter's info.

Sorry Johnson for chasing your thread into details.
Finally there are multiple possibilities available and it is up to you to judge.

P.S.
Don't have a cold smps on hand, otherwise I could show the same for that construction.
Edit: 'Same' does not mean any information about the result, but same action of disassembling and measuring.
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Last edited by ChocoHolic; 9th November 2011 at 07:08 PM.
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Old 10th November 2011, 10:23 PM   #32
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Quote:
Originally Posted by JohnsonAV View Post
Ok, so this topic has gotten to be over my head. I really don't know what any of you are talking about when you mention creepage and double insulation, etc. Some explanation would be appreciated....
Please note, my vote and pictures were for the hypex smps1200 (not 400).
But these smps are designed for double instantanous power, it is likely that the 400W version will do the job in your case.

Trying some simple explanations on creepages, clearances, basic insulation, double insulation, protection class I, protection class II:

Creepage:
Distance between to isolated parts, measured along the surface of the isolator.

Clearance:
Distance between to isolated parts. Measured not on a surface, but shortest way through the air.

Protection class I:
All conductive touchable parts of the device have a low impedance connection to protective earth.
In this case the isolation between these touchable parts and high voltage areas needs to fulfill basic insulation, requires moderate creepages, moderate clearances and no requirement on isolation thickness.
High pot test voltage for 300V operating voltage: 2kV

Protection class II:
Conductive touchable parts can be floating.
In this case the isolation between these touchable parts and high voltage areas needs to fulfill double/reinforced insulation, requires huge creepages, huge clearances and at least 0.4mm isolation thickness for single layer insulations.
High pot test voltage for 300V operating voltage: 4kV

Detailed descriptions, figures and lots of further mandatory safety requirements you will find the approx. 180 pages of the EN60065
UL standards are not identical at all, but use a lot of similar vocabulary.
Unfortunately even safety standards are not available for free.
IMHO standards with almost the character of a law must be free.
The high price of EN60065 really made angry, when I bought it.
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Old 10th November 2011, 10:39 PM   #33
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Quote:
Originally Posted by ChocoHolic View Post
Please note, my vote and pictures were for the hypex smps1200 (not 400).
But these smps are designed for double instantanous power, it is likely that the 400W version will do the job in your case.
Is that per SDS-258 or will that feed both with one SMPS?

BTW, thanks for the definitions, I know what you mean about "purchasing" UL spec's.

So my question to the definitions is, why is creepage and clearance important? what happens if those dimensions not maintained?

Thanks for all the knowledge!
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Old 11th November 2011, 06:56 PM   #34
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When talking about the 400W-type, I intended that you could use one for one SDS258.

Why creepages and clearances?
Electrical currents can 'creep' accross surfaces.
It also depends on the material and degree of pollution and humidity how easy this might happen.
Also Electricity can 'jump' ==> arcing. How easy it can jump also depends on humidity and air pressure.
The values in the standards bring down the likelihood that we get zapped close to zero. If those dimensions are not maintained the likelihood of being zapped will grow.
Imagine you are standing in front of an power outlet where somebody has removed the plastic cover: How close do you want to put your fingers to the life metal contacts?

...of course we could now bring up the philosophic question whether people who do risky jobs, sports & hobbies, would agree to accept less creepage and less clearance, because the overall risk assessment of their life style indicates heavy imbalance of risk in the non electrical areas...
But since I broke my back I stopped motorbiking and suddenly even properly isolated power outlets became the most dangerous part in my life.
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Old 11th November 2011, 07:57 PM   #35
AP2 is offline AP2  Italy
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I do not want to be cruel but I would like to add ..
A DIY is free to experiment and build long as they remain within the private testing. (even if it is stupid to risk his life)
But can not market a product out of the minimum standards required to ensure safety, (in Italy it is criminal), in China maybe is good .. I think
Everyone wants to build SMPS low prices .. thanks to a ton of savings in equipment, special tests (all required especially on the transformer) and component certifications.
I think that when a customer chooses a product, should not look only at the price.

Last edited by AP2; 11th November 2011 at 08:04 PM.
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Old 11th November 2011, 09:13 PM   #36
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[QUOTE=ChocoHolic;2777094]

Obviously "conductive touchable parts" refers to the operational configuration with cover on, but does it also apply to service configuration, i.e. covers removed?
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Old 12th November 2011, 10:16 AM   #37
marce is offline marce  United Kingdom
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FYI
creapage and clearance info can be found on this site...
The Evaluation of Spacings in Electronic Product Design
The standards are pretty much applicable all over the world, whether they are policed is a different matter.
Personaly I use the same standards for any DIY PCB stuff I do as I do when I am doing a 'proffesional' (ie one I'm getting paid for) PCB... spent 8 years doing PCB's for generator set controllers so we had to be on the ball with our creepage and clearance, as we sold to the whole world. I like UL because they do test and give you feed back.
I am of the opinion that if you are going to do this sort of thing as a hobby then because of the dangers you should work to the same regulations as everybody else.
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Old 12th November 2011, 10:32 AM   #38
AP2 is offline AP2  Italy
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I agree completely.
UL or other certifications (country dependent), may accept or not accept the device. This is a guarantee as EMC certification.
However, fortunately the majority of which are present in this forum, I think that abides by the rules ... I hope
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Old 12th November 2011, 03:37 PM   #39
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[QUOTE=noah katz;2778235]
Quote:
Originally Posted by ChocoHolic View Post

Obviously "conductive touchable parts" refers to the operational configuration with cover on, but does it also apply to service configuration, i.e. covers removed?
No, if you remove the cover, then you will find plenty of dangerous areas easy to touch. That's why there are warning labels- in order to prevent opening by people without the specific skill set.

EDIT:
Here a link with safety rules, not about design, but about working on electrical appliances.
http://www.economypoint.org/t/the-fi...ety-rules.html

Last edited by ChocoHolic; 12th November 2011 at 04:04 PM.
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Old 14th November 2011, 02:09 PM   #40
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Quote:
Originally Posted by AP2 View Post
Hi,
which model of amplifier you will need the SMPS? (A-B / D)
where it is used the amp? (home.. SUB, PA, etc.)

Regards
Sorry to get back to this so late. It's a class D amp module (two to be exact) and it is a design for professional application. Ground (Earth) is necessary.
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