17 replies to this topic

[BradfordNC]

interesting how up until the release of 3442 psi tanks a couple of years ago, the 5-thread DIN connector was called 200 bar.

now, everyone calls it 232 bar.

whats also interesting is how people think the 200, 232, and 300 bar connectors were created for the scuba industry, at the industries whim.

however, the DIN connectors predate the scuba industry. the DIN standards were drawn up in Germany back when a little ego-maniac made the trains run on time.

the standards were originaly drawn up for the downstream application of the compressed gas, and not with the rating of the cylinder. it deals with the compatibility of the downstream tool (or regulator) with the gas supply.


here is a decent explanation i have copied from a much more learned source.

The Deutsches Institut Für Normung (DIN) is a German standards setting organization similar to our American National Standards Institute (ANSI) and Compressed Gas Association (CGA). DIN 477 is a specification that recommends cylinder valve outlet and connector designs for specific types of gases and pressures based upon safety considerations. These various designs have deliberate incompatibilities to preclude the possibility of errors when handling different types of compressed gases at differing working pressures. The two valve outlets and connectors of interest for divers are the DIN 477 No. 13 and the DIN 477 No. 56 (formerly No. 50), both designated for use with compressed air. The DIN 477 valve and regulator fittings are most widely used outside the U.S. The regulator first stage DIN connector is a male screw type, and instead of clamping on to the outside of the valve as does the yoke, it screws directly into the female DIN outlet of the valve. The sealing O-ring is held in the end of the regulator connector rather than in the face of the outlet. The DIN 477 system, with it's captured o-ring design, has proven to be very reliable for use with SCUBA.
Outlet/Connector #13 is from DIN 477 part 1 - for cylinders with test pressure ratings up to 300 bar and is commonly referred to in the SCUBA industry by the slang term "200 bar", probably because most cylinders with 300 bar test pressures have working pressures in the 200 bar range. Outlet/Connector #56 is from DIN 477 part 5 - for cylinders with test pressure ratings up to 450 bar and is commonly referred to in the SCUBA industry by the slang term "300 bar". The two designs are nearly identical, but the #56 valve outlet is deliberately deeper so the shorter #13 connector will not be long enough to seat properly. This is a safety feature to prevent connecting a low pressure device to a high pressure supply. It's important to understand that the "200 bar" or "300 bar" descriptions are just slang terms that have nothing to do with the pressure ratings of the outlets and connectors themselves!

[Dive_Girl]

dang darlin'! Great info!

[ScubaDadMiami]

I agree. Excellent information.