Rebreather World - View Single Post

Shaunzxr · 6th May 2008, 17:14

The batteries were duracell brand new reading 1.59 at start of dive
They read 1.4 during the dive. I think they were 1.3 at the end of the dive
The 5 minutes was on 15-12m stop, so no temp change. The temp was about 8 degree's
I didn't notice the voltage reading when the primary came back on.
This is the first time it has happened
It was an inland dive site so no salt.

I have tried my best to find conductive lubricant in the UK.
If anybody can point me in the right direction that would be great.

Quote: (Originally Posted by jradomski)

When you say the batteries were fine.. what was the voltage before the dive?? was the air alot warmer than the water??

You say it came back after 5 minutes.. did you ascend to warmer water??
after it came back on what was the voltage reading??

Has this happened only once??

These are questions to ask to help determine if its a handset problem or just a crap cell.. my personal recommendation is that if the voltage is less than 1.5v for an alkaline (when idle) on the surface change the cell.... I have seen way to many 1.5v batteries come out of the box at 1.4v and less...

With the ss cap and spring Its unlikely that you will see corrosion, also with the large surface area on the cap/spring contact issues are not that likely.. but some oxidation on the contact at the bottom of the battery compartment is possible and since its a AA cell there is a relatively small contact area.. and if the battery has any oxidation its possible that a "dead" spot can form... Use a pencil eraser on the positive contact in the compartment.. Pressure will warp the case slightly then release its deformation, so a contact issue is possible...

Personally I would like to see a spring loaded contact at the bottom as well.. to help isolate changes in the the case from the battery..

anytime a user replacable primary cell is used, the fact that its not a soldered contact means that contacts have to be checked regularly for oxidation..

On every dive computer that I own that has replaceble batteries I always use a bit of conductive lubricant on both the positive and negative terminals to reduce the change of a contact issue.. Don't use too much or it will create its own problems...

Before I started using it on my vr3, I had alot of intermittent lock ups.. on my explorer it stopped the occasional computer reset.. On both the explorer and vr3 I always had the lockup or reset upon accent.. usually somewhere around 50% of maximum depth...

with the limited info so far I would look at the positive terminal...

6th May 2008, 17:14	#125 (permalink)
Shaunzxr Inspo Luver Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Apr 2005 Location: UK, midlands Posts: 87	Re: HammerHead Revisions and Issues The batteries were duracell brand new reading 1.59 at start of dive They read 1.4 during the dive. I think they were 1.3 at the end of the dive The 5 minutes was on 15-12m stop, so no temp change. The temp was about 8 degree's I didn't notice the voltage reading when the primary came back on. This is the first time it has happened It was an inland dive site so no salt. I have tried my best to find conductive lubricant in the UK. If anybody can point me in the right direction that would be great. Quote: (Originally Posted by jradomski) When you say the batteries were fine.. what was the voltage before the dive?? was the air alot warmer than the water?? You say it came back after 5 minutes.. did you ascend to warmer water?? after it came back on what was the voltage reading?? Has this happened only once?? These are questions to ask to help determine if its a handset problem or just a crap cell.. my personal recommendation is that if the voltage is less than 1.5v for an alkaline (when idle) on the surface change the cell.... I have seen way to many 1.5v batteries come out of the box at 1.4v and less... With the ss cap and spring Its unlikely that you will see corrosion, also with the large surface area on the cap/spring contact issues are not that likely.. but some oxidation on the contact at the bottom of the battery compartment is possible and since its a AA cell there is a relatively small contact area.. and if the battery has any oxidation its possible that a "dead" spot can form... Use a pencil eraser on the positive contact in the compartment.. Pressure will warp the case slightly then release its deformation, so a contact issue is possible... Personally I would like to see a spring loaded contact at the bottom as well.. to help isolate changes in the the case from the battery.. anytime a user replacable primary cell is used, the fact that its not a soldered contact means that contacts have to be checked regularly for oxidation.. On every dive computer that I own that has replaceble batteries I always use a bit of conductive lubricant on both the positive and negative terminals to reduce the change of a contact issue.. Don't use too much or it will create its own problems... Before I started using it on my vr3, I had alot of intermittent lock ups.. on my explorer it stopped the occasional computer reset.. On both the explorer and vr3 I always had the lockup or reset upon accent.. usually somewhere around 50% of maximum depth... with the limited info so far I would look at the positive terminal...
(Offline)