Hi,
I'm looking to use a particular terminal block for mains voltages (220v). The top-level descriptions says it is suitable, but when I check the datasheet (under the heading 'general') it says.....
Rated voltage (III/3) 63 V
Rated voltage (III/2) 160 V
Rated voltage (II/2) 320 V
How do I know which one actually applies?
thanks
How do I know which one actually applies?
Post a link and let us all look at it. Maybe you are missing something.
here's the datasheet (top of 2nd page)
The top level description of the item on the vendors page quotes the 3rd voltage (320v) which made me assume it's suitable for mains use - although I admit the pitch of 2.54mm seems a little close
I think the rated voltage depends upon use and the standards applied.
Nominal voltage UN is 125 V.
Find out what the UN refers to.
Rated voltage (II/2) is 320V, does not say AC or DC.
Could apply possibly only if the board is conformally coated or some such
when I search for the strings like "Rated Voltage (III/3)", I get results for stuff like the IEC Category Ratings, which makes sense that Category II would have a higher rating than Category III. I don't know what the /# means, someone else more versed in the lingo will need to weigh in.
What i find with problems like this is that if you are not in the 'club', getting hold of the relevant standards documents costs loads.
although I admit the pitch of 2.54mm seems a little close
Since there's a physical barrier between the terminals, I wouldn't worry about it. (The insulated wires in a power cord are closer.)
Now, if you're building something for production & sale you'd need to meet the requirements of your country.
DVDdoug:
Since there's a physical barrier between the terminals, I wouldn't worry about it. (The insulated wires in a power cord are closer.)Now, if you're building something for production & sale you'd need to meet the requirements of your country.
I wasn't really concerned about the closeness on the PCB, but when it comes to wiring in a mains cable, then one teeny-tiny strand of live 220volt cable a tenth of an inch away from a similar neutral cable makes me a little nervous - I'll probably double space them.
Those are the certification standards that it was tested too, the problem is the standards are not published expensive (the Club) so how does anyone know what was actually tested. Certification is done to sell into a market (club's monopoly) and since it is VDE it is most likely the EU. Anyway, they don't really mean anything unless you want to pay to see the standard. Actually, that part is allowed by an impressive list of clubs.
There are two tolerances involved, one to adjacent conductors and one to ground/earth.
Fulliautomatix:
here's the datasheet (top of 2nd page)The top level description of the item on the vendors page quotes the 3rd voltage (320v) which made me assume it's suitable for mains use - although I admit the pitch of 2.54mm seems a little close
Pitch 2.54mm is insanely small for terminal block, too fiddly to bother with in my experience.
For high voltage go for 5mm.
ron_sutherland:
Those are the certification standards that it was tested too, the problem is the standards are not published (the Club) so how does anyone know what was actually tested.
That is simply not true.
There is no exclusive club, all standards are published and available, although there is a charge for them. The whole point about a standard is that every one should be able to see them, they are not secrete. It is a legal requirement that any regulatory requirement has to be available to anyone.
All the members of the conspiratorial club of your imagining have to pay the same price as any individual to buy the published standards. You might say that these prices are too high and form some sort of barrier to entry, and that would be so, but these standards are fully published.
I have seen this from both sides, both as an individual and also as a member of the "club". Back in 1985 I payed the vast sum, as it was then, of £80, for a telecoms standard for modems, so I could have the information to build a modem. I was not blocked from buying it.
Years later, when I worked in regulatory compliance, the company had to buy the relevant standards documents and supplements, just like anyone else.
I think you mis understood me.
In an organisation that needs these things there is generally a subscription that gives ready access to these documents.
For joe bloggs it costs lots of money to access individual documents.
I came across this several years ago with BS standards.
Previously i had free access.
When i needed them privately they cost me something like 30 £ + individually.
Similar applies for access to learned articles and patents
It was not you but ron_sutherland I was replying to, who seemed to suggest that these standards were secrete.
The last standard I got from UL (or was it CSA) cost over 500$US, so think/say whatever you want about how open that is, but I call bull shit. Patents are completely open and free to look at, and Standards for an open market should also be free and available to look at, what is the point of a paywall if not to make a club.
what is the point of a paywall if not to make a club.
The point of paying is that the standards committees have to be paid and payment from the publication of their standards is one of the few sources of income.
The committees are formed of people that are paid by the companies interested in the standard. So you (Mike) are saying the monies collected by UL or CSA for me to access the standard has to to do with creating the standard or some future version of it. I have doubts.
The committees are formed of people that are paid by the companies interested in the standard.
The companies do not pay people on the comitties.
Interesting, so where I worked in the past the people that did some work on standards got paid for their time by the outfit I was working for. They did not do the work on their own time, and they did not get a check from UL.
Well that is in stark contrast to what I witnessed in the UK.