Why are German domestic DIN standards used so much?

[RogerL_5041474]

Why are German DIN standards used so much on European cars and caravans which have by law to comply with EN standards?

DIN is simply the old German domestic eqivalent of the old British BSI. For countries in the EC, the EuroNorm (EN)has largely superceded both BSI and DIN. There seem to be any number of aspects where DIN is used in preference to EN standards. Why?

For cars, the EN standard for power output is kW, Britain used to use BHP (the Americans still do) and the Germans used to use PS. So why are virtually all power outputs expressed in PS, when this has no validity outside Germany.

For caravans, the EN standard connections are 12N + 12S, but an increasing number of cars / caravans are being fitted with the old German domestic DIN 13-pin connection.

Why has the UK changed all it's standards from BSI to EN as a condition of our membership of the Common Market only to find that the old (pre-Common Market) domestic German DIN standard is geadually being introduced?

There's no point in having standards if we don't all use them!

 

[keith_5081818]

I dont know, but im still using BHP & i'll go on using it as its the only one i understand.

I thought the yanks used something else, like cubic inch, as every time i see them on the telly, talking about their hot rods, i can never understand what they mean.

 

[Lutz]

Actually, the PS is not a legal unit in Germany any more either although it is still commonly used in day-to-day conversation. Officially, however, such as in the vehicle registration papers, power output is expressed in kW only.

As for the 13-pin DIN connection, this is not an old German standard but it was introduced in the early 90's when rear foglamps were made mandatory for trailers and the old 7-pin connection did not provide enough pins for this feature. In Germany it was felt that the market would reject the idea of having to use 2 plugs so a 13-pin connection was born. Actually, there are three 13-pin systems in use in Germany, the most common being the DIN/Jaeger system but there is also a WeSt system and a Multicon system. The advantage of the latter is that certain combinations do not need an adapter but on the other hand they are not quite as reliable.

The DIN/Jaeger system is actually an ISO standard (ISO 11446).

 

[JohnE1]

I dont know, but im still using BHP & i'll go on using it as its the only one i understand.

I thought the yanks used something else, like cubic inch, as every time i see them on the telly, talking about their hot rods, i can never understand what they mean.

Keith. The Yanks use cu.inch as we use litre. ie. a measure of cylinder capacity.

 

[rob_jax]

Hi Roger,

Aside from my normal job running a company in Rotterdam, I'm the UK representative to Europe on (techincal) fuel standards for motor vehicles - CEN TC19.

At this time, there are three important standards bodies:

ISO which is a global standard, recognised Worldwide.

EN, as you say, is the European Standard, specified and agreed by the various technical commitees in Europe. Recognised by all European governments, these EN standards have the country standards bureau "stamp" automatically applied.

For instance the EN standard for Diesel is EN 590, and in the UK you will see EN BS 590 on the fuel pump, in Germany it will say EN DIN 590.

Country only standards, like BS (UK), DIN (Germany) and NEN (Holland). There is no point having an individual country standard for something like Diesel or other commodities that are freely traded across Europe.

Each county is still free to create it's own country standard for "stuff" that is perhaps only relevant to that country - for example the UK 13 Amp household plug and socket.

So I can't agree with your statement.

Robert

 

[RogerL_5041474]

Yes, I understand that countries can use their own standards in addition to EN requirements, and long may that remain the case.

So why aren't DIN standards restricted to domestic German products.

Surely all products sold in the UK should comply with EN or BSI standards, not some non-standard domestic specification from another country.

 

[mike_5041102]

Just a little more about 13 pin plugs. The Multicon is no longer in production. Although Jaeger is the standard, Multicon-WeSt is still being supplied on new caravans, by Chateau group and Swift (European models) amongst others. Many people rightly prefer the Multicon-WeSt because of its compatibility with the old 7 pin without the need of adapters. Why Jaeger ever became the standard is beyond me, must have something to do with the Germany caravan industry being the largest in Europe. Pin diameters of the Multicon-WeSt are identical to, or greater than, the pins used by Jaeger therefore it will not be less reliable. Poor reliability is only true of the old Multicon connector.

 

[Lutz]

The whole idea of having a standard is to have a common design which ensures interchangeability. Whether this standard is BSI, SAE, EN, DIN, ISO or any other is immaterial so long as there is a common agreement. If the industry has agreed to adopt certain DIN standards, that fulfils the purpose. As DIN standards probably have the most widespread coverage, it makes sense to adopt them unless there's is a sound reason not to, such specific market requirements.

 

[RogerL_5041474]

I agree with you totally, Lutz, but in these cases (PS and 13-pin connectors) these DIN standards HAVEN'T been adopted as EN standards.

 

[Lutz]

No, but as I wrote earlier, PS isn't a legal unit in Germany either and the 13-pin DIN connector is an ISO standard.

There is also a commercial reason for the adoption of the 13-pin connector. In Germany, vehicles loose their type approval as soon as any technical changes are made, and that includes fitting a towbar. The vehicle registration book must also reflect the presence of the towbar, if fitted. So, in order to avoid the hassle of having to take one's car to the German equivalent of the MOT after installation and then going to the vehicle licensing office to have the registration book changed, most people prefer to order their towbars factory fitted. In that way, all the paperwork is done before the car is delivered to the dealer. Consequently, the volumes involved are considerable and it just isn't economical for the car manufacturers to offer specific 12N & 12S connections only for the UK market.

 

[RogerL_5041474]

If find your argument about cost of change for the UK market somewhat strange.

Car manufacturers will readily make RHD just for the UK, and have different suspension settings for the UK, Italy, France etc. These changes must cost a lot more to engineer than a change of towing electric connectors.

It's not just German manufacturers imposing domestic requirements on the UK, they're also imposed on France and the rest of Europe.

Even American manufacturers (GM / Ford) are starting to impose German domestic standards, even on cars built and sold in the UK.

If the German domestic requirement is so good and so popular, why hasn't it been adopted as an EN standard?

 

[rob_jax]

Hi Roger,

You wrote: "So why aren't DIN standards restricted to domestic German products"

Quite easy to answer, and this does not just apply to DIN, but BS, NEN and other standards bodies.

There may be a country standard that is freely used by other countries. A good example of this (in petroleum refining) are the American ASTM standards or UK based Institute of Petroleum (IP) standards, where there is persuasive technical expertise that makes it compelling for other countries to accept that standard.

There may be a country standard that is accepted by another country and used as such until it has been translated and re-written to become a native standard.

Robert

 

[rob_jax]

Hi Roger,

You wrote "If the German domestic requirement is so good and so popular, why hasn't it been adopted as an EN standard?"

Because there's no point. If an ISO standard exists it takes precedence over EN, which itself takes precedence over BS or DIN.

Robert

 

[RogerL_5041474]

I understand full well that ISO standards take precedence over EN, which in turn take precedence over BS and DIN standards.

The fact that some European manufacturers, of cars and caravans, can choose whether to use an EN standard or a different ISO standard makes a complete nonsense of "standards".

 

[Lutz]

Even if not everybody has agreed on one common standard, that's better than every country or every manufacturer going their own way. A reduction in the number of standards is of benefit to everyone but one has to accept the fact that national interests are often a major stumbling block.

 

[RogerL_5041474]

Yes, Lutz, a reduction in the number of standards is a good idea. But in this case standards are proliferating.

In the UK the used to be just one standard in use for car - caravan connections. It was the 12N+12S. Now we have two standards as the 13-pin connection is being imposed on the UK market.