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WreckWriter once bubbled...
I think I know why you're losing the stop. In the config there's a checkbox for "O2 window affect". What this does is remove un-needed stops from the profile. Looking at the profile you have, its not very aggressive so I bet it doesn't really need a 70 foot stop. Do you have this turned on?

If so, try this: Be sure you have "extended stops" checked, set a minimum gas switch time (I use 5 min) then turn OFF (uncheck) "O2 window affect" and re-calc the dive. Let me know if that works.

Don't get an older version, VPM-B is supposed to be safer. I've dived it fairly hard with no problems.

WW

Will try this. I have played with the O2 Window switch, but not enough to get a feel for what it did.

Thanks WW.

MD
 
I get a 70 foot stop either way.

O2 window off:

------------------

V-Planner 3.10 by R. Hemingway, VPM code by Erik C. Baker.

Decompression model: VPM-B

DIVE PLAN
Surface interval = 2 day 0 hr 0 min.
Altitude = 0ft
Conservatism = + 2

Dec to 150ft (3) on Trimix 22.0/45.0, 50ft/min descent.
Level 150ft 22:00 (25) on Trimix 22.0/45.0, 1.22 ppO2, 43ft END
Asc to 100ft (25) on Trimix 22.0/45.0, -60ft/min ascent.
Asc to 80ft (26) on Trimix 22.0/45.0, -30ft/min ascent.
Stop at 80ft 0:30 (27) on Trimix 22.0/45.0, 0.75 ppO2, 14ft END
Stop at 70ft 5:00 (32) on Nitrox 50.0, 1.56 ppO2, 32ft END
Stop at 60ft 1:00 (33) on Nitrox 50.0, 1.41 ppO2, 26ft END
Stop at 50ft 1:00 (34) on Nitrox 50.0, 1.26 ppO2, 20ft END
Stop at 40ft 1:00 (35) on Nitrox 50.0, 1.10 ppO2, 13ft END
Stop at 30ft 1:00 (36) on Nitrox 50.0, 0.95 ppO2, 7ft END
Stop at 20ft 12:00 (48) on Nitrox 50.0, 0.80 ppO2, 1ft END
Stop at 20ft 5:00 (53) on Trimix 22.0/45.0, 0.35 ppO2, 0ft END
Stop at 20ft 3:00 (56) on Nitrox 50.0, 0.80 ppO2, 1ft END
Asc to sfc. (56) on Nitrox 50.0, -30ft/min ascent.

Off gassing starts at 108.8 ft

OTU's this dive: 58
CNS Total: 22.5%

99.6 cu ft Trimix 22.0/45.0
24.6 cu ft Nitrox 50.0
124.2 cu ft TOTAL


DIVE PLAN COMPLETE

------------------

O2 window ON:

V-Planner 3.10 by R. Hemingway, VPM code by Erik C. Baker.

Decompression model: VPM-B

DIVE PLAN
Surface interval = 2 day 0 hr 0 min.
Altitude = 0ft
Conservatism = + 2

Dec to 150ft (3) on Trimix 22.0/45.0, 50ft/min descent.
Level 150ft 22:00 (25) on Trimix 22.0/45.0, 1.22 ppO2, 43ft END
Asc to 100ft (25) on Trimix 22.0/45.0, -60ft/min ascent.
Asc to 80ft (26) on Trimix 22.0/45.0, -30ft/min ascent.
Stop at 80ft 0:30 (27) on Trimix 22.0/45.0, 0.75 ppO2, 14ft END
Stop at 70ft 5:00 (32) on Nitrox 50.0, 1.56 ppO2, 32ft END
Stop at 30ft 3:00 (36) on Nitrox 50.0, 0.95 ppO2, 7ft END
Stop at 20ft 12:00 (48) on Nitrox 50.0, 0.80 ppO2, 1ft END
Stop at 20ft 5:00 (53) on Trimix 22.0/45.0, 0.35 ppO2, 0ft END
Stop at 20ft 3:00 (56) on Nitrox 50.0, 0.80 ppO2, 1ft END
Asc to sfc. (56) on Nitrox 50.0, -30ft/min ascent.

Off gassing starts at 108.8 ft

OTU's this dive: 57
CNS Total: 22.1%

99.6 cu ft Trimix 22.0/45.0
24.0 cu ft Nitrox 50.0
123.6 cu ft TOTAL


DIVE PLAN COMPLETE

----------------------


Notice the fairly significant increase in RT over Mike's example which shows the changes in VPM-B

WW
 
Why does VPM give you a backgas break on 50/50 for deco gas at your shallow stop with a PO2 well under 1.0?

That doesn't seem to make much sense... am I missing something here?
 
WreckWriter once bubbled...
I get a 70 foot stop either way.

O2 window ON:

V-Planner 3.10 by R. Hemingway, VPM code by Erik C. Baker.

Decompression model: VPM-B

DIVE PLAN
Surface interval = 2 day 0 hr 0 min.
Altitude = 0ft
Conservatism = + 2

Dec to 150ft (3) on Trimix 22.0/45.0, 50ft/min descent.
Level 150ft 22:00 (25) on Trimix 22.0/45.0, 1.22 ppO2, 43ft END
Asc to 100ft (25) on Trimix 22.0/45.0, -60ft/min ascent.
Asc to 80ft (26) on Trimix 22.0/45.0, -30ft/min ascent.
Stop at 80ft 0:30 (27) on Trimix 22.0/45.0, 0.75 ppO2, 14ft END
Stop at 70ft 5:00 (32) on Nitrox 50.0, 1.56 ppO2, 32ft END
Stop at 30ft 3:00 (36) on Nitrox 50.0, 0.95 ppO2, 7ft END
Stop at 20ft 12:00 (48) on Nitrox 50.0, 0.80 ppO2, 1ft END
Stop at 20ft 5:00 (53) on Trimix 22.0/45.0, 0.35 ppO2, 0ft END
Stop at 20ft 3:00 (56) on Nitrox 50.0, 0.80 ppO2, 1ft END
Asc to sfc. (56) on Nitrox 50.0, -30ft/min ascent.

Off gassing starts at 108.8 ft

OTU's this dive: 57
CNS Total: 22.1%

99.6 cu ft Trimix 22.0/45.0
24.0 cu ft Nitrox 50.0
123.6 cu ft TOTAL


DIVE PLAN COMPLETE

----------------------


Notice the fairly significant increase in RT over Mike's example which shows the changes in VPM-B

WW

The only difference I see is you are using a significantly higher ascent rate than I did above 100' (30 vs 10).

I may have seen this, but how did you set in the gas break time at 20'?
 
Genesis once bubbled...
Why does VPM give you a backgas break on 50/50 for deco gas at your shallow stop with a PO2 well under 1.0?

That doesn't seem to make much sense... am I missing something here?

It shouldn't but....

Because I have it set to give air breaks on the 20 foot stop after 12 minutes (normally would be on O2) and I forgot to uncheck the air break box when I did these calcs. It actually seems to be a glitch because it shouldn't give breaks on 50% O2. I'll have to look into that.

WW
 
I just noticed that and said "huh?", because with the total CNS clock and the PO2 exposures in that dive during deco I couldn't imagine how the program would have come up with the need for a backgas break at the 20' stop :)
 
Genesis once bubbled...
I just noticed that and said "huh?", because with the total CNS clock and the PO2 exposures in that dive during deco I couldn't imagine how the program would have come up with the need for a backgas break at the 20' stop :)

I didn't notice it until you mentioned it as I almost always use 2 deco gasses. I just wrote Ross about it.

WW
 
Hello All,

1/ The extended stop option, will only be applied, if an actual stop was required at that level. i.e if the deco does not start until 50 ft, then no extention will occur at 70ft for a 50% gas switch.

2/ O2 window affect - In the example dive here, an extented stop for 5 minutes at 70ft, has removed the 60 and 50 ft stops. The O2 window affect allows this due to the over stopping done at 70ft, from the extended stop.
Without the O2 window affect, the missing stops would have been the minimum of 1 minute each.

3/ Air breaks are tricky. I'm guessing you have the depth switch set at 20 or 30 ft? Any of the conditions will trip the airbreaks, but only if it fits the timing sequences set.

Regards
--
Ross Hemingway
 
Where do I get palm VPM? I currently have d-plan and j-plan that I like alot. I just like running different profiles to see the difference.
Thanks
ADAM
 
http://cavediveflorida.com/Rum_House.htm

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