HammerHead Revisions and Issues

Claudio · 1st August 2006, 11:50

I possess the first version of the metallic HH, ordered October 2005 and receiver December.
First found problem: with alkaline batteries AA 1.5v the autonomy is absolutely insufficient (I does not understand the 6 hours that I have read.). Many times to the end of a dive (approximately an hour or little more) the secondary one are blocked for insufficient voltage. A normal new AA alcaline battery (1,61 v at the beginnig), to the end of a dive of an has a voltage of 1.43 v, and this me seems already critical… The alkaline batteries is only an alternative (like emergency) and only for short recreational immersions. I am not in agreement with whom they think that a monitoring of the residual autonomy of the batteries on display is superfluous, if the recommendations are followed, on the contrary I task it is almost indispensabie (is too many the variable ones that influence on this parameter).
Other problem: unexpected extinction of the secondary one during the immersion, above all in depth (problem that has had also a my friend) and successive spontaneous relighting. Problem of electrical contact on the poles of the batteries, as I have read? it can are given. Sure the thing is a little alarming one….also because completely accidental. I have bathed the contacts with least lubricating that I use for flash sub (the Hugyphot) and the problem apparently is resolved, but I do not know if this is accidental or resolutive.
The more serious problem :The boxes them are corroded; I had read of the problem, but it is worse than how much I imagined. The corrosion does not regard only the external nichel-plate, but also and above all the metallic alloy of the boxes. The phenomenon has been obvious since the first divein sea water and happens in points situates on the the angles; when started, it always continues on the same place, aggravating itself more and more. If I watch the box carefully during the dive, I see very well the metal that he corrodes himself!. After only seven dives in seq water the aesthetic damages are much obvious, and could be transformed in work them....
the lack of the manual shutdown of the electronic (to the end of the dive) is cause of a useless discharge of the batteries. Also with the lessened shutdown time (2 min), often the electronics remain on for much longer periods (it remain in humid atmosphere).

I must say of being enough satisfied of the HH, but these problems must absolutely be resolved endured. Other update would be many profits (scrubber monitoring, PC interface, smaller dimensions, dives in high mountains, etc), but the change of the "old" boxes them (in total guarantee, I hope) with the new (Anodized? SS?) and the possibility to have a valid monitoring of the batteries is absolute priority

***jradomski*** · 1st August 2006, 13:18

Quote: (Originally Posted by Claudio)

I possess the first version of the metallic HH, ordered October 2005 and receiver December.
First found problem: with alkaline batteries AA 1.5v the autonomy is absolutely insufficient (I does not understand the 6 hours that I have read.). Many times to the end of a dive (approximately an hour or little more) the secondary one are blocked for insufficient voltage. A normal new AA alcaline battery (1,61 v at the beginnig), to the end of a dive of an has a voltage of 1.43 v, and this me seems already critical… The alkaline batteries is only an alternative (like emergency) and only for short recreational immersions. I am not in agreement with whom they think that a monitoring of the residual autonomy of the batteries on display is superfluous, if the recommendations are followed, on the contrary I task it is almost indispensabie (is too many the variable ones that influence on this parameter).
Other problem: unexpected extinction of the secondary one during the immersion, above all in depth (problem that has had also a my friend) and successive spontaneous relighting. Problem of electrical contact on the poles of the batteries, as I have read? it can are given. Sure the thing is a little alarming one….also because completely accidental. I have bathed the contacts with least lubricating that I use for flash sub (the Hugyphot) and the problem apparently is resolved, but I do not know if this is accidental or resolutive.
The more serious problem :The boxes them are corroded; I had read of the problem, but it is worse than how much I imagined. The corrosion does not regard only the external nichel-plate, but also and above all the metallic alloy of the boxes. The phenomenon has been obvious since the first divein sea water and happens in points situates on the the angles; when started, it always continues on the same place, aggravating itself more and more. If I watch the box carefully during the dive, I see very well the metal that he corrodes himself!. After only seven dives in seq water the aesthetic damages are much obvious, and could be transformed in work them....
the lack of the manual shutdown of the electronic (to the end of the dive) is cause of a useless discharge of the batteries. Also with the lessened shutdown time (2 min), often the electronics remain on for much longer periods (it remain in humid atmosphere).

I must say of being enough satisfied of the HH, but these problems must absolutely be resolved endured. Other update would be many profits (scrubber monitoring, PC interface, smaller dimensions, dives in high mountains, etc), but the change of the "old" boxes them (in total guarantee, I hope) with the new (Anodized? SS?) and the possibility to have a valid monitoring of the batteries is absolute priority

If you have corrosion issues contact Kevin..

AA alkalines should definately last at least 6 hours.. on the testing I have done I was getting about 1.5x-2X that (depended on the brand) with heavy solenoid firing, Kevin said he was getting similiar results.. AA alkaline batteries are considered good (by battery manufacturer ratings) down to 0.8v, the HH can operate down to 0.9v as long as the current is available.. so a drop to 1.43v is not much..

also the typical discharge or an alkaline cell is like this, there is a relatively fast drop off initially, then the voltage drop becomes "flatter" then there is a fast drop off near the end of life..
The dropoff from about 1.5 to 1.3 is pretty quick, from 1.3 to 1.1 takes alot longer, from 1.1 to dead is quick again..

If you don't get the handsets replaced, crush the battery cap threads slightly, and enlarge the hole around the wet switch (only seems to be necessary on some units).. it will solve the 2 problems you have had..

Also if the wetswitches are truely dry and no residue, the go to sleep function should immediately put the units to sleep..

Claudio · 1st August 2006, 15:25

Joe,
- I am trying my HH. I measure the voltage of the battery, little a discharge but still good, still good, as you say (1,21 v). Naturally it is the voltage measured not "under cargo". I insert the battery and the HH is power on, but then he extinguishes himself endured. He relights himself spontaneously and then he extinguishes himself, in an infinite series… In the primary and in the secondary...The HH does not work. I insert a new battery and all he works well. You say that all she would have to work until 0.8 volt. In my HH it is not true.
- I have written to Kevin of the problem of the corrosion and also of other, but nobody answers
- the function “go to sleep” is only in the primary but not in the secondary... ???

***diverklondike*** · 1st August 2006, 15:40

Quote: (Originally Posted by Claudio)

Joe,
- I am trying my HH. I measure the voltage of the battery, little a discharge but still good, to how much you assert (1,21 v). Naturally it is the voltage measured not "under cargo". I insert the battery and the HH is power on, but then he extinguishes himself endured. He relights himself spontaneously and then he extinguishes himself, in an infinite series… In the primary and in the secondary...The HH does not work. I insert a new battery and all he works well. You say that all she would have to work until 0.8 volt. In my HH it is not true.
- I have written to Kevin of the problem of the corrosion and also of other, but nobody answers
- the function “go to sleep” is only in the primary but not in the secondary... ???

Claudio,

Here are a couple comments and suggestions.

1) Not sure what type of battery you are using but what you have discribed and the situation sounds like a low battery. I use inexpensive AA Alkaline batteries and change them when I change my scrubber. For what it's worth I have taken new batteries out of a pak only to find that they are "dead".

2) The go to sleep is only on the primary.

3) Not sure when you tried to reach Kevin. He is out of town this week. I would suggest that you call him and or resend an email on Monday. He does have a very aggresive spam filter.

Dive Safe.

Mark

***jradomski*** · 1st August 2006, 17:09

Quote: (Originally Posted by Claudio)

Joe,
- I am trying my HH. I measure the voltage of the battery, little a discharge but still good, still good, as you say (1,21 v). Naturally it is the voltage measured not "under cargo". I insert the battery and the HH is power on, but then he extinguishes himself endured. He relights himself spontaneously and then he extinguishes himself, in an infinite series… In the primary and in the secondary...The HH does not work. I insert a new battery and all he works well. You say that all she would have to work until 0.8 volt. In my HH it is not true.
- I have written to Kevin of the problem of the corrosion and also of other, but nobody answers
- the function “go to sleep” is only in the primary but not in the secondary... ???

aa alkalines are rated down to .8v (by battery manufacturers) the HH will stop functioning usualy around .9 or 1.0 depending on the cell under load.. You are describing a dead battery,, reading the open circuit voltage (no load) really doesnt mean much, some cells read fairly high when dead..

test your batteries under abut a 30-40ma load.. a 47ohm resistor across the battery, while measuring it should give you a reasonable reading..

if you are getting just a few hours, then I think the unit needs evaluation..

Claudio · 1st August 2006, 20:21

Nick and Joe,
I use Duracell or Energizer batteries and the problem has ALWAYS introduced and with ALL the batteries that I have used. The problem without a doubt is caused from the batteries, because when I use the new battery all works well. I do not understand if it is my HH that for some reason consumes more energy of yours, but what I say to you it is that the batteries, when they are under 1.3 volt gives ALWAYS this problem to me… You changed the batteries to every change of scrubber (3 hours?). I practically change them to every dive!!!… I will feel what of it I think Kevin when it will answer to me.
Thanks

***jradomski*** · 2nd August 2006, 00:08

Quote: (Originally Posted by Claudio)

Nick and Joe,
I use Duracell or Energizer batteries and the problem has ALWAYS introduced and with ALL the batteries that I have used. The problem without a doubt is caused from the batteries, because when I use the new battery all works well. I do not understand if it is my HH that for some reason consumes more energy of yours, but what I say to you it is that the batteries, when they are under 1.3 volt gives ALWAYS this problem to me… You changed the batteries to every change of scrubber (3 hours?). I practically change them to every dive!!!… I will feel what of it I think Kevin when it will answer to me.
Thanks

I think the unit needs evaluation.. I recently wanted to test the duration of AA alkaline cells in the most recent units (I usualy use lithium cells), so I put the batteries in a week before I planned to use them, I then did 2 pool sessions (6-7 hours total time, probably about 4 hours on the loop) and then did 2 ow dives of 1 hr each and the cells worked fine.. I didnt measure the voltage (I should have) but that was as far as I was interested in using the cells.

Tecdiverfl · 2nd August 2006, 01:52

Are you diving it with the solenoid firing or flying it manually?
I was getting a reboot after 25 minutes with a fresh AA in 80 degree water.
Mine is on the way back from Dive Rite after spending about a month and a half with Kevin for that and several other issues.

***jradomski*** · 2nd August 2006, 06:05

Quote: (Originally Posted by Tecdiverfl)

Are you diving it with the solenoid firing or flying it manually?
I was getting a reboot after 25 minutes with a fresh AA in 80 degree water.
Mine is on the way back from Dive Rite after spending about a month and a half with Kevin for that and several other issues.

All the above testing was done letting the unit do its job....

was the 25 minutes on an ascent?? if so doesnt sound like a battery issue more like a contact issue that can be resolved simply by crushing the threads on the battery cap just a bit..

to get an idea about estimated duration, lets look at the typical aa alkaline battery.. they are generally rated about 2850 mAh, since most of the system runs at ~3v we have to cut that rating in half to figure average current draw.. so 1425mah,, the usable range for the HH is about 10%-20% less than what the typical manufacturere says the battery is good (they count it good to .8v) so lets take off 20%, now we are at 1160mAh, a typical charge pump will average around 80% efficiency, so we are down to 928 mAh..

The HH uses on average about 40ma while it is active (no flashing leds, backlight or solenoid firing), so in theory while active it should last about 23 hours in this condition, which is in the ballpark of what I have observed.. This number will vary based on temperature and battery but its a good estimation as a baseline... now you have to add in solenoid firing and backlight use.. the more current you pull the more you have to derate the cells.. someone who uses the backlight alot will find considerably shorter life than just the extra draw of the light since it will derate the cells further..

for example the rating of 2850ma is based on a 25ma draw (so in the HH avg draw case its a bit less), but if we go up to a constant 250mA draw the life is now under 2000mAh..

The average diver probably has the solenoid on about 4 seconds every minute (more if the IP is lower) for most of the dive (unless you are working or ascending) lets call that 7% of the time for some wiggle room.. that means for 7% of the time the average draw is about 6 times higher (the solenoid is 6v so we have to double the current draw again)..

the easiest way to guesstimate this out is to take 7% of 928 =64.96 and multiply it by 6 = 389.76, rounded to 390... so 7% of the time consumes 390mAh of the usefule life.. leaving 538ah or about 13 hours , this compares pretty well to some informal testing that I did on the unit under pressure while trying to maintain a po2 ( I was getting ~12 hours (at room temp) before killing the unit)..

If we use the backlight it will also decrease this number, as will more frequent/longer firing of the solenoid....

The potential life of the cell is reduced by about 50% at 0 C (alkaline cells do poorly in cold temperatures)..

I HAVEN'T measured the current draw on the latest version of the handsets, the 40ma number was based on the previous revision of hardware, but the numbers should still be in the ballpark.

paulraymaekers · 2nd August 2006, 09:46

Quote: (Originally Posted by jradomski)

I HAVEN'T measured the current draw on the latest version of the handsets, the 40ma number was based on the previous revision of hardware, but the numbers should still be in the ballpark.

last time I measured without firing, it was 16mA working, 400microA sleeping

regards
paul

1st August 2006, 11:50	#21 (permalink)
Claudio New Member Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Other CCR Join Date: Nov 2005 Location: ITALY - Trento Posts: 58	Re: HammerHead Revisions and Issues I possess the first version of the metallic HH, ordered October 2005 and receiver December. First found problem: with alkaline batteries AA 1.5v the autonomy is absolutely insufficient (I does not understand the 6 hours that I have read.). Many times to the end of a dive (approximately an hour or little more) the secondary one are blocked for insufficient voltage. A normal new AA alcaline battery (1,61 v at the beginnig), to the end of a dive of an has a voltage of 1.43 v, and this me seems already critical… The alkaline batteries is only an alternative (like emergency) and only for short recreational immersions. I am not in agreement with whom they think that a monitoring of the residual autonomy of the batteries on display is superfluous, if the recommendations are followed, on the contrary I task it is almost indispensabie (is too many the variable ones that influence on this parameter). Other problem: unexpected extinction of the secondary one during the immersion, above all in depth (problem that has had also a my friend) and successive spontaneous relighting. Problem of electrical contact on the poles of the batteries, as I have read? it can are given. Sure the thing is a little alarming one….also because completely accidental. I have bathed the contacts with least lubricating that I use for flash sub (the Hugyphot) and the problem apparently is resolved, but I do not know if this is accidental or resolutive. The more serious problem :The boxes them are corroded; I had read of the problem, but it is worse than how much I imagined. The corrosion does not regard only the external nichel-plate, but also and above all the metallic alloy of the boxes. The phenomenon has been obvious since the first divein sea water and happens in points situates on the the angles; when started, it always continues on the same place, aggravating itself more and more. If I watch the box carefully during the dive, I see very well the metal that he corrodes himself!. After only seven dives in seq water the aesthetic damages are much obvious, and could be transformed in work them.... the lack of the manual shutdown of the electronic (to the end of the dive) is cause of a useless discharge of the batteries. Also with the lessened shutdown time (2 min), often the electronics remain on for much longer periods (it remain in humid atmosphere). I must say of being enough satisfied of the HH, but these problems must absolutely be resolved endured. Other update would be many profits (scrubber monitoring, PC interface, smaller dimensions, dives in high mountains, etc), but the change of the "old" boxes them (in total guarantee, I hope) with the new (Anodized? SS?) and the possibility to have a valid monitoring of the batteries is absolute priority
(Online)

1st August 2006, 13:18	#22 (permalink)
*jradomski* Moderator Current Rebreather/s: Inspiration Classic Sport Kiss Optima rEvo Other CCR Home Build Other Rebreather/s: Inspiration Vision Evolution Megalodon Classic Kiss rEvo Other CCR Home Build Join Date: Mar 2005 Location: "Da" Bronx Posts: 2,817	Re: HammerHead Revisions and Issues Quote: (Originally Posted by Claudio) I possess the first version of the metallic HH, ordered October 2005 and receiver December. First found problem: with alkaline batteries AA 1.5v the autonomy is absolutely insufficient (I does not understand the 6 hours that I have read.). Many times to the end of a dive (approximately an hour or little more) the secondary one are blocked for insufficient voltage. A normal new AA alcaline battery (1,61 v at the beginnig), to the end of a dive of an has a voltage of 1.43 v, and this me seems already critical… The alkaline batteries is only an alternative (like emergency) and only for short recreational immersions. I am not in agreement with whom they think that a monitoring of the residual autonomy of the batteries on display is superfluous, if the recommendations are followed, on the contrary I task it is almost indispensabie (is too many the variable ones that influence on this parameter). Other problem: unexpected extinction of the secondary one during the immersion, above all in depth (problem that has had also a my friend) and successive spontaneous relighting. Problem of electrical contact on the poles of the batteries, as I have read? it can are given. Sure the thing is a little alarming one….also because completely accidental. I have bathed the contacts with least lubricating that I use for flash sub (the Hugyphot) and the problem apparently is resolved, but I do not know if this is accidental or resolutive. The more serious problem :The boxes them are corroded; I had read of the problem, but it is worse than how much I imagined. The corrosion does not regard only the external nichel-plate, but also and above all the metallic alloy of the boxes. The phenomenon has been obvious since the first divein sea water and happens in points situates on the the angles; when started, it always continues on the same place, aggravating itself more and more. If I watch the box carefully during the dive, I see very well the metal that he corrodes himself!. After only seven dives in seq water the aesthetic damages are much obvious, and could be transformed in work them.... the lack of the manual shutdown of the electronic (to the end of the dive) is cause of a useless discharge of the batteries. Also with the lessened shutdown time (2 min), often the electronics remain on for much longer periods (it remain in humid atmosphere). I must say of being enough satisfied of the HH, but these problems must absolutely be resolved endured. Other update would be many profits (scrubber monitoring, PC interface, smaller dimensions, dives in high mountains, etc), but the change of the "old" boxes them (in total guarantee, I hope) with the new (Anodized? SS?) and the possibility to have a valid monitoring of the batteries is absolute priority If you have corrosion issues contact Kevin.. AA alkalines should definately last at least 6 hours.. on the testing I have done I was getting about 1.5x-2X that (depended on the brand) with heavy solenoid firing, Kevin said he was getting similiar results.. AA alkaline batteries are considered good (by battery manufacturer ratings) down to 0.8v, the HH can operate down to 0.9v as long as the current is available.. so a drop to 1.43v is not much.. also the typical discharge or an alkaline cell is like this, there is a relatively fast drop off initially, then the voltage drop becomes "flatter" then there is a fast drop off near the end of life.. The dropoff from about 1.5 to 1.3 is pretty quick, from 1.3 to 1.1 takes alot longer, from 1.1 to dead is quick again.. If you don't get the handsets replaced, crush the battery cap threads slightly, and enlarge the hole around the wet switch (only seems to be necessary on some units).. it will solve the 2 problems you have had.. Also if the wetswitches are truely dry and no residue, the go to sleep function should immediately put the units to sleep.. __________________ Joe Radomski CCR Trimix Instructor Trainer ANDI Instructor Trainer Director #10 All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated. Last edited by jradomski : 1st August 2006 at 13:23.
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1st August 2006, 15:25	#23 (permalink)
Claudio New Member Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Other CCR Join Date: Nov 2005 Location: ITALY - Trento Posts: 58	Re: HammerHead Revisions and Issues Joe, - I am trying my HH. I measure the voltage of the battery, little a discharge but still good, still good, as you say (1,21 v). Naturally it is the voltage measured not "under cargo". I insert the battery and the HH is power on, but then he extinguishes himself endured. He relights himself spontaneously and then he extinguishes himself, in an infinite series… In the primary and in the secondary...The HH does not work. I insert a new battery and all he works well. You say that all she would have to work until 0.8 volt. In my HH it is not true. - I have written to Kevin of the problem of the corrosion and also of other, but nobody answers - the function “go to sleep” is only in the primary but not in the secondary... ??? Last edited by Claudio : 1st August 2006 at 15:35.
(Online)

1st August 2006, 15:40	#24 (permalink)
*diverklondike* Moderator Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Inspiration Classic Other CCR Join Date: Oct 2005 Location: Delaware, USA Posts: 1,462	Re: HammerHead Revisions and Issues Quote: (Originally Posted by Claudio) Joe, - I am trying my HH. I measure the voltage of the battery, little a discharge but still good, to how much you assert (1,21 v). Naturally it is the voltage measured not "under cargo". I insert the battery and the HH is power on, but then he extinguishes himself endured. He relights himself spontaneously and then he extinguishes himself, in an infinite series… In the primary and in the secondary...The HH does not work. I insert a new battery and all he works well. You say that all she would have to work until 0.8 volt. In my HH it is not true. - I have written to Kevin of the problem of the corrosion and also of other, but nobody answers - the function “go to sleep” is only in the primary but not in the secondary... ??? Claudio, Here are a couple comments and suggestions. 1) Not sure what type of battery you are using but what you have discribed and the situation sounds like a low battery. I use inexpensive AA Alkaline batteries and change them when I change my scrubber. For what it's worth I have taken new batteries out of a pak only to find that they are "dead". 2) The go to sleep is only on the primary. 3) Not sure when you tried to reach Kevin. He is out of town this week. I would suggest that you call him and or resend an email on Monday. He does have a very aggresive spam filter. Dive Safe. Mark
(Online)

1st August 2006, 17:09	#25 (permalink)
*jradomski* Moderator Current Rebreather/s: Inspiration Classic Sport Kiss Optima rEvo Other CCR Home Build Other Rebreather/s: Inspiration Vision Evolution Megalodon Classic Kiss rEvo Other CCR Home Build Join Date: Mar 2005 Location: "Da" Bronx Posts: 2,817	Re: HammerHead Revisions and Issues Quote: (Originally Posted by Claudio) Joe, - I am trying my HH. I measure the voltage of the battery, little a discharge but still good, still good, as you say (1,21 v). Naturally it is the voltage measured not "under cargo". I insert the battery and the HH is power on, but then he extinguishes himself endured. He relights himself spontaneously and then he extinguishes himself, in an infinite series… In the primary and in the secondary...The HH does not work. I insert a new battery and all he works well. You say that all she would have to work until 0.8 volt. In my HH it is not true. - I have written to Kevin of the problem of the corrosion and also of other, but nobody answers - the function “go to sleep” is only in the primary but not in the secondary... ??? aa alkalines are rated down to .8v (by battery manufacturers) the HH will stop functioning usualy around .9 or 1.0 depending on the cell under load.. You are describing a dead battery,, reading the open circuit voltage (no load) really doesnt mean much, some cells read fairly high when dead.. test your batteries under abut a 30-40ma load.. a 47ohm resistor across the battery, while measuring it should give you a reasonable reading.. if you are getting just a few hours, then I think the unit needs evaluation.. __________________ Joe Radomski CCR Trimix Instructor Trainer ANDI Instructor Trainer Director #10 All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated.
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1st August 2006, 20:21	#26 (permalink)
Claudio New Member Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Other CCR Join Date: Nov 2005 Location: ITALY - Trento Posts: 58	Re: HammerHead Revisions and Issues Nick and Joe, I use Duracell or Energizer batteries and the problem has ALWAYS introduced and with ALL the batteries that I have used. The problem without a doubt is caused from the batteries, because when I use the new battery all works well. I do not understand if it is my HH that for some reason consumes more energy of yours, but what I say to you it is that the batteries, when they are under 1.3 volt gives ALWAYS this problem to me… You changed the batteries to every change of scrubber (3 hours?). I practically change them to every dive!!!… I will feel what of it I think Kevin when it will answer to me. Thanks
(Online)

2nd August 2006, 00:08	#27 (permalink)
*jradomski* Moderator Current Rebreather/s: Inspiration Classic Sport Kiss Optima rEvo Other CCR Home Build Other Rebreather/s: Inspiration Vision Evolution Megalodon Classic Kiss rEvo Other CCR Home Build Join Date: Mar 2005 Location: "Da" Bronx Posts: 2,817	Re: HammerHead Revisions and Issues Quote: (Originally Posted by Claudio) Nick and Joe, I use Duracell or Energizer batteries and the problem has ALWAYS introduced and with ALL the batteries that I have used. The problem without a doubt is caused from the batteries, because when I use the new battery all works well. I do not understand if it is my HH that for some reason consumes more energy of yours, but what I say to you it is that the batteries, when they are under 1.3 volt gives ALWAYS this problem to me… You changed the batteries to every change of scrubber (3 hours?). I practically change them to every dive!!!… I will feel what of it I think Kevin when it will answer to me. Thanks I think the unit needs evaluation.. I recently wanted to test the duration of AA alkaline cells in the most recent units (I usualy use lithium cells), so I put the batteries in a week before I planned to use them, I then did 2 pool sessions (6-7 hours total time, probably about 4 hours on the loop) and then did 2 ow dives of 1 hr each and the cells worked fine.. I didnt measure the voltage (I should have) but that was as far as I was interested in using the cells. __________________ Joe Radomski CCR Trimix Instructor Trainer ANDI Instructor Trainer Director #10 All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated.
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2nd August 2006, 01:52	#28 (permalink)
Tecdiverfl New Member Current Rebreather/s: Optima Other Rebreather/s: Join Date: Oct 2005 Location: Delray Beach, FL Posts: 67	Re: HammerHead Revisions and Issues Are you diving it with the solenoid firing or flying it manually? I was getting a reboot after 25 minutes with a fresh AA in 80 degree water. Mine is on the way back from Dive Rite after spending about a month and a half with Kevin for that and several other issues.
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2nd August 2006, 06:05	#29 (permalink)
*jradomski* Moderator Current Rebreather/s: Inspiration Classic Sport Kiss Optima rEvo Other CCR Home Build Other Rebreather/s: Inspiration Vision Evolution Megalodon Classic Kiss rEvo Other CCR Home Build Join Date: Mar 2005 Location: "Da" Bronx Posts: 2,817	Re: HammerHead Revisions and Issues Quote: (Originally Posted by Tecdiverfl) Are you diving it with the solenoid firing or flying it manually? I was getting a reboot after 25 minutes with a fresh AA in 80 degree water. Mine is on the way back from Dive Rite after spending about a month and a half with Kevin for that and several other issues. All the above testing was done letting the unit do its job.... was the 25 minutes on an ascent?? if so doesnt sound like a battery issue more like a contact issue that can be resolved simply by crushing the threads on the battery cap just a bit.. to get an idea about estimated duration, lets look at the typical aa alkaline battery.. they are generally rated about 2850 mAh, since most of the system runs at ~3v we have to cut that rating in half to figure average current draw.. so 1425mah,, the usable range for the HH is about 10%-20% less than what the typical manufacturere says the battery is good (they count it good to .8v) so lets take off 20%, now we are at 1160mAh, a typical charge pump will average around 80% efficiency, so we are down to 928 mAh.. The HH uses on average about 40ma while it is active (no flashing leds, backlight or solenoid firing), so in theory while active it should last about 23 hours in this condition, which is in the ballpark of what I have observed.. This number will vary based on temperature and battery but its a good estimation as a baseline... now you have to add in solenoid firing and backlight use.. the more current you pull the more you have to derate the cells.. someone who uses the backlight alot will find considerably shorter life than just the extra draw of the light since it will derate the cells further.. for example the rating of 2850ma is based on a 25ma draw (so in the HH avg draw case its a bit less), but if we go up to a constant 250mA draw the life is now under 2000mAh.. The average diver probably has the solenoid on about 4 seconds every minute (more if the IP is lower) for most of the dive (unless you are working or ascending) lets call that 7% of the time for some wiggle room.. that means for 7% of the time the average draw is about 6 times higher (the solenoid is 6v so we have to double the current draw again).. the easiest way to guesstimate this out is to take 7% of 928 =64.96 and multiply it by 6 = 389.76, rounded to 390... so 7% of the time consumes 390mAh of the usefule life.. leaving 538ah or about 13 hours , this compares pretty well to some informal testing that I did on the unit under pressure while trying to maintain a po2 ( I was getting ~12 hours (at room temp) before killing the unit).. If we use the backlight it will also decrease this number, as will more frequent/longer firing of the solenoid.... The potential life of the cell is reduced by about 50% at 0 C (alkaline cells do poorly in cold temperatures).. I HAVEN'T measured the current draw on the latest version of the handsets, the 40ma number was based on the previous revision of hardware, but the numbers should still be in the ballpark. __________________ Joe Radomski CCR Trimix Instructor Trainer ANDI Instructor Trainer Director #10 All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated. Last edited by jradomski : 2nd August 2006 at 06:51.
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2nd August 2006, 09:46	#30 (permalink)
paulraymaekers rEvo's daddy Current Rebreather/s: rEvo Other CCR Home Build Other Rebreather/s: rEvo Other CCR Home Build Join Date: May 2005 Location: belgium Posts: 1,384	Re: HammerHead Revisions and Issues Quote: (Originally Posted by jradomski) I HAVEN'T measured the current draw on the latest version of the handsets, the 40ma number was based on the previous revision of hardware, but the numbers should still be in the ballpark. last time I measured without firing, it was 16mA working, 400microA sleeping regards paul __________________ www.rEvo-rebreathers.com .... the earth is flat, Elvis is alive, and radial scrubbers give longer dwell time than axials...
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