Forskellen på to seiko modeller ?

[hannover_dk]

Joepete Skrev:The SAT term is just an expression, John, and has nothing to do with "withstanding mixed gas", as I understand things. I might be wrong though, but until we get one of the professional diver´s on to this thread, this is how I understand things:

The whole point is that when You go for a professional dive at perhaps 175 meters, You use "mixed gas" AND you need to use a helium chamber when ascending. It is therefor crucial that Your watch (if using such an "old-timer" ) can cope with helium and take the very big pressur at those depths.

I am not quite sure from where You get the 10 minute vs 35 minutes ... ? I would trust the MM300 professional diver´s watch to be descended as long as the diver would want it to be

I have sent SK an e-mail to get his assistance on this - I think we need it

Lad os bare gå til dansk igen - sikker på Willy sagtens følger os. Jeg tror du har ret JoePete, at det med forlænget tid, ikke har at gøre med at uret er sikkert i forhold til at ha på i lang tid under vand - men jeg fik det fra, at ISO 6425 foregår i så lang tids test - i forhold til den "billigere ISO"
Som et par eksempler i uddrag fra ISO 6425 med tiden som faktor
ISO 6425 water resistance testing of a diver's watch consists of:
Immersion of the watch in 30 cm of water for 50 hours.
Immersion of the watch in a suitable pressure vessel and subjecting it to 125% of the rated pressure for 2 hours.
(som kunne være for at dykkeren kunne være nede de der 2 timer)

I beskrivelse for Seiko står det jo klart, at mixed gas diving IKKE refererer til mixed gas som man har i flasken til de lange dyk (hvor man ikke kan bruge alm luft eller ilt), men til mixed gas i helium kammer - netop for at sik:

Seiko SBBN007 Professional Diver's 300 m for mixed-gas diving.
For mixed-gas diving the watch has to be immersed in a suitable pressure vessel and subjecting it to 125% of the rated pressure for 15 days in a (helium enriched) breathing gas mix. Subsequently the overpressure shall be reduced to normal pressure within 3 minutes. No evidence of water intrusion, condensation or problems caused by internal overpressure are allowed.

Så det er nok sådan, at urene ikke specielt kan være længere nede men at testen kræver længere tid, og det giver jo ekstra sikkehed for tiden, og mixed gas er helium kammer.
vh