Pelagian -is this the right choice?

wearypanda · 19th February 2007, 19:56

Having decided to go the mCCR route I eventually narrowed my choice down to either the COPIS Meg or the Pelagian.

After spending many hours reading (mainly here, asking questions and thinking a lot about which CCR is the right choice for me, I have pretty much decided that the Pelagian is the right unit for me.

The Pelagian has quite a few attributes and features which I feel give it an edge. These include:=

Diluent injection designed to blow condensation off sensors and give almost instant sensor validation
Compact size
Needle valve controlled O2 metering
Uses lots of OC parts making it a lot easier to fix problems without having to order parts frommanufacturer
Low volume head and designed so that cylinders have valves at top make for better trim

The Pelagian is cheaper than the COPIS but this is certainly not the most important factor.

The downsides to the Pelagian all stem from the fact that it is a new unit and it is made in Thailand. So, currently there are very few instructors (training has to be done in Thailand - what a hardship!) and manufacturer's support is a relatively unknown quantity. I am also a little concerned that there might be design flaws yet to reveal themselves as the unit becomes more extensive used.

I would greatly appreciate any advice or thoughts you may have on this choice before I finally part with my hard earned cash.

Thanks in advance.

diverklondike · 19th February 2007, 20:52

Quote: (Originally Posted by wearypanda)

Having decided to go the mCCR route I eventually narrowed my choice down to either the COPIS Meg or the Pelagian.

After spending many hours reading (mainly here, asking questions and thinking a lot about which CCR is the right choice for me, I have pretty much decided that the Pelagian is the right unit for me.

The Pelagian has quite a few attributes and features which I feel give it an edge. These include:=

Diluent injection designed to blow condensation off sensors and give almost instant sensor validation
Compact size
Needle valve controlled O2 metering
Uses lots of OC parts making it a lot easier to fix problems without having to order parts frommanufacturer
Low volume head and designed so that cylinders have valves at top make for better trim

The Pelagian is cheaper than the COPIS but this is certainly not the most important factor.

The downsides to the Pelagian all stem from the fact that it is a new unit and it is made in Thailand. So, currently there are very few instructors (training has to be done in Thailand - what a hardship!) and manufacturer's support is a relatively unknown quantity. I am also a little concerned that there might be design flaws yet to reveal themselves as the unit becomes more extensive used.

I would greatly appreciate any advice or thoughts you may have on this choice before I finally part with my hard earned cash.

Thanks in advance.

While I do not own a Meg, here are a couple points to consider...

All of your down sides are significant ones... The Meg has been dove to many extremes and done well...

1) If you feel the Copis Meg is a little larger than you want, I would expect that Leon would sell you a Mini-Copis Meg. Ron M... Can you confirm this??

2) If you wanted I am sure that you could invert the bottles on the Meg. I have seen a few people doing this...

3) The ability to blow dil accross the sensor face is a nice to have but my experiance is that this has not been an issue for the Meg as it applies to condensation. Note that cell technology has improved quite a bit over the years in it's ability to handle condensation.

Two other last items...

You can upgrade a Copis it to a full ECCR...

The Meg has an excellent resale value if you were to choose to sell it...

Good Luck and Dive Safe!

Mark

dave t · 19th February 2007, 21:41

Depending on how the pelagian blows gas over the sensors can be a plus or a minus. Directing a stream of gas directly onto the cell face can be detrimental to the cells health. Was ok when the cis-luner first used that trick as the cells then had a gause face which was more robust, but now with the ptfe faced cells they are a bit delicate

looks like a nice unit though well thought out!

Dave

silent running · 20th February 2007, 05:26

Quote: (Originally Posted by wearypanda)

Having decided to go the mCCR route I eventually narrowed my choice down to either the COPIS Meg or the Pelagian.

After spending many hours reading (mainly here, asking questions and thinking a lot about which CCR is the right choice for me, I have pretty much decided that the Pelagian is the right unit for me.

The Pelagian has quite a few attributes and features which I feel give it an edge. These include:=

Diluent injection designed to blow condensation off sensors and give almost instant sensor validation
Compact size
Needle valve controlled O2 metering
Uses lots of OC parts making it a lot easier to fix problems without having to order parts frommanufacturer
Low volume head and designed so that cylinders have valves at top make for better trim

The Pelagian is cheaper than the COPIS but this is certainly not the most important factor.

The downsides to the Pelagian all stem from the fact that it is a new unit and it is made in Thailand. So, currently there are very few instructors (training has to be done in Thailand - what a hardship!) and manufacturer's support is a relatively unknown quantity. I am also a little concerned that there might be design flaws yet to reveal themselves as the unit becomes more extensive used.

I would greatly appreciate any advice or thoughts you may have on this choice before I finally part with my hard earned cash.

Thanks in advance.

Hello wp, what Dave said about sensor faces being a bit fragile is my understanding as well. So unless the unit has some kind of restrictor to really limit the dil flow, I don't think it's a very good idea to blow dil directly at the sensor faces. I would also wonder about the effect of the difference btw the warm loop temp and the fresh, possibly very cold gas hitting the sensor face...

Otherwise, the Pelagian looks well thought out. I wonder how the under-arm CLs breathe compared to standard OTS CLs? The inner bladder CL idea seems like a good idea for durability and resistance to punctures/snags. And I wonder if the Pelagian will ever have a radial scrubber. You can buy radials aftermarket for the Meg.

I can't tell how the sensors are wired, if they're KISS like independent circuits for the 2 sensor display and where the battery is located, but the idea of having the 3rd sensor going to a computer seems like a good one. And I'm guessing that the COPIS Meg has a HUD and the Pelagian does not. I think every unit should have a HUD.

But the Pelagian has the needle valve and from my indirect experience diving with a friend of mine and his buddies who use needle valved Dolphins, it seemed like the way to go for MCCR. They would adjust the flow once or twice during the dive and never had to hit the add button. It worked well for high and low workloads and the needle valve itself was easy to clean.

Tough choice, lots of things to think about but it seems like you'd need more info about the Pelagian to make a good choice... -Andy

rogeringebo · 20th February 2007, 08:43

Quote: (Originally Posted by diverklondike)

While I do not own a Meg, here are a couple points to consider...

All of your down sides are significant ones... The Meg has been dove to many extremes and done well...

1) If you feel the Copis Meg is a little larger than you want, I would expect that Leon would sell you a Mini-Copis Meg. Ron M... Can you confirm this??

2) If you wanted I am sure that you could invert the bottles on the Meg. I have seen a few people doing this...

3) The ability to blow dil accross the sensor face is a nice to have but my experiance is that this has not been an issue for the Meg as it applies to condensation. Note that cell technology has improved quite a bit over the years in it's ability to handle condensation.

Two other last items...

You can upgrade a Copis it to a full ECCR...

The Meg has an excellent resale value if you were to choose to sell it...

Good Luck and Dive Safe!

Mark

Hi Guys!
Here is my view on the matter..
I own and dive both a Megalodon with solenoid and a Pelagian.
I work as a diveinstructor and dive rebreathers almost every day. I started diving a KISS because I like the idea of controlling my O2 flow myself without electronics. After testing the Pelagian prototype I ordered one straight away and sold my KISS. While waiting for my Pelagian I bought and dived my Meg with much joy. I always dive it manual with the electronics set below the setpoint I choose to dive,like a parashute sort of. I still have my Meg and I think it is the best ECCR on the market but prefer my Pelagian because

-Its much more compact

-Lighter

-It can be taken on a airplane as carry on, I think it is the lightest rebreather on the market that is made for serious deep dives.

-Its made so you can put on any tanks available,all you need is a piece of webbing (or a weightbelt) and the put on what ever is available on the boat,island or resort you are. No need for Tigermounts or ratteling G-snaps with hoseclamps that turn out to be to short. I have even dived with 12 liter tanks (80cf)

-Better trim because airspace in head is kept to a minimum to avoid vertical trim. Meg have a huge metal tube with lots of unneccesray air in it which mean more lead on you hips. Pelagian is built for having tankvalves/regs up so trim will improve and no need for weights high up to be horizontal. I dive my Meg the same way btw

-Easier to take apart and handle.

-Hold setpoint much better

-Much bigger scrubber (about 3,5kg of Sofnolime)

-Curved lungs that stay out of your way

-Will be possible to order with supercompact BOV soon. Smallest on the market but with the biggest inner bore for good weight of breathing.

-You can plug in Vr3 or HS Explorer on third cell for complete redundant
readout (I dive like this)

-Sensor validation via ADV,breath out a half breath through nose and inhale slowly,ADV will kick in a blow DIL over cells and you see straight away which cell is off...no need for complete flush and loss of gas.
The gas blow in an angle across the cell and not straight on the membrane. Its maine objective is to help you check which cell or cells are off. The loss of condensation is just a nice bonus.

-No theorethical depth limit

You are right,there are no electronic kit you can buy for it at the moment but Andy dont want electronics handeling your O2 feed,Thats the whole idea with the Pelagian. No HUD,no solenoid,no voting,no computer deciding whats best for you. You have to decide for yourself which means no nasty surprises with stuck electronics feeding O2 at the wrong time or morse code blinking HUD that might jam or show wrong colour (if you even can see the difference in tropical waters? I can not)
Iam quite sure that you could fit Hammerhead or Shearwater electronics to your Pelagian if you want to.
I hope this helps to clarify some things.

Dive safe!

Roger Ingebo
PADI MSDT
KISS diver
Megalodon diver
Pelagian instructor

Rebreatherlab · 20th February 2007, 10:46

Very true.

Cis Lunar MK5P feeds DIL through a tight nozzle straight to the cell membranes. Many divers have tried the current Teledyne R17D cells, but usually get problems with cells going way off for a week after diving due to the standard hydrophobic membrane.

To address this issue we have fed the Dil through a 5,5 mm bore from a 40 degree angle. The speed of the gas flow is controlled by the diver as it is triggered from the ADV, i.e. you dump half a breath from your nose and inhale slowly. As long as you hear the ADV hissing the DIL is displacing the surrounding gas and you can work out what is realistic. Typically the PO2 will read slightly higher than DIL PO2 due to the tiny influence of the surrounding gas, flow of gas etc. Theoretically also the temperature difference will have a small effect. As the idea is to get a quick reality check a few times during a dive, or at any time the two readouts disagree, it is of minor importance.

To give a practical example: with air dil the read out may show appox Po2 1,1 at 40 msw instead of the mathematically correct 1,045.

To test the long term effect, the first prototype was dived for one year with out any problems. The prototype used a smaller bore feed nozzle and inflator style feed actuator, so the speed of the gas flow was faster and more difficult to control than what we have now with the ADV and divers lungs being the actuator.

The wiring is as follows:

Molex connector to wire, soldered, epoxy sealed and heat shrinked.
Wire to battery compartment with epoxy seal, battery compartment to external gland, (with expoxy sealed plastic internal body). External cable jacket is gas sealed on both ends and carries signal for both cells and battery cable to the shared display housing. PCB and all componenets are sealed and will survive a flood in seawater. All componenents will survive inveresed poplarity and if plus and minus is shorted only the PCB plus trace will fry. This can be fixed quite easily. To prevent a short the battery is kept in its own sealed compartment.

To test the integrity of the seals we pressurize the loop to 4 bar with the calibration plug to the display housing open. Any minor leak after a few minutes would be visible on the PO2 read outs.

The motto while designing the head and all other parts was to provide a very compact and light weight CCR to the travelling diver that did not compromise on duration, WOB and flexibility. It took 6 months to design the head and I feel that we have reached what we set out to do.

As the main internal diameter of the scrubber is 126, 8 mm, I don't think we will be focusing on a radial scrubber. Personally I also dive a Cis MK5P which has a radial can and I always get more milage out of the Pelagian standard axial scrubber and a lot less abrupt CO2 break through if pushed to the limit.

WOB is significantly lower on the Pelagian than on the CIS and many other current units so why radial when the present axial works fine?

We are currently working on UK marketing so hopefully it will not be long until people can see and try the units with out having to come for a nice training holiday to Thailand!

Best,

Andy
REBREATHER LAB

Quote: (Originally Posted by dave t)

Depending on how the pelagian blows gas over the sensors can be a plus or a minus. Directing a stream of gas directly onto the cell face can be detrimental to the cells health. Was ok when the cis-luner first used that trick as the cells then had a gause face which was more robust, but now with the ptfe faced cells they are a bit delicate

looks like a nice unit though well thought out!

Dave

wearypanda · 20th February 2007, 20:10

Thanks so much everyone who responded.

One design aspect that I was not aware of until today is that on the Pelagian Diluent can only be added to the loop through the ADV. This means (I think) that to do a diluent flush or indeed any addition of diluent it is necessary to vent air from the loop by breathing into the mask and your next breath will draw diluent into the loop through the ADV. It is the ADV which blows diluent across the sensors giving you an almost instant validation.

I must admit I am not sure about this. I have heard that ADV's sometimes malfunction and that it is common to have a valve which enables the diver to stop the ADV working should it start putting air into the loop unecessarily.

Trouble is, I simply do not have enough knowledge at this stage to know whether this is a neat and minimalist design feature or something which could cause problems. I am probably misunderstanding something here.

What do you all think? Should I be concerned?

Rebreatherlab · 20th February 2007, 20:45

The loop is purged as follows;

1. Roll on your back, (horizontal facing the surface).
2. Pull the dumpvalve on the exhale counter lung and the ADV will purge and stop when you relese the dump cord. Cross your arms if you want to reduce the flexible part of the loop to conserve gas.

If you want a secondary input for DIL to the loop, just buy a dry suit inflator valve from Apex, cut a hole in the inhale CL and connect the feed hose to your bail out or on board DIL.

OR

Order the up coming BOV lower section, connect to the present DSV and ad Dil to the loop by taking a breath from the OC BOV and exahle in to the loop.

If you want to ad a inline on/off switch for the ADV you might want to wait until we provide one as we will make one that connects direct from the 1st stage for easy reach. If the ADV freeflows and freeze in the open position you would with out the on off switch simply close the dil cylinder valve and wait a few minutes. It will not likely stay frozen for long with the warm loop gas surrounding the lever mechanism. If in the same time need to purge the loop due to high PO2, it will be very easy! If you need to momentarily ad some DIL to your wing, then feather the valve while inflating the wing and shut down the valve after. You might also want to consider routing the wing inflation hose to your bail out.

Cheers,

Andy

Quote: (Originally Posted by wearypanda)

Thanks so much everyone who responded.

One design aspect that I was not aware of until today is that on the Pelagian Diluent can only be added to the loop through the ADV. This means (I think) that to do a diluent flush or indeed any addition of diluent it is necessary to vent air from the loop by breathing into the mask and your next breath will draw diluent into the loop through the ADV. It is the ADV which blows diluent across the sensors giving you an almost instant validation.

I must admit I am not sure about this. I have heard that ADV's sometimes malfunction and that it is common to have a valve which enables the diver to stop the ADV working should it start putting air into the loop unecessarily.

Trouble is, I simply do not have enough knowledge at this stage to know whether this is a neat and minimalist design feature or something which could cause problems. I am probably misunderstanding something here.

What do you all think? Should I be concerned?

JonnyB · 20th February 2007, 21:02

Quote: (Originally Posted by wearypanda)

Thanks so much everyone who responded.

One design aspect that I was not aware of until today is that on the Pelagian Diluent can only be added to the loop through the ADV. This means (I think) that to do a diluent flush or indeed any addition of diluent it is necessary to vent air from the loop by breathing into the mask and your next breath will draw diluent into the loop through the ADV. It is the ADV which blows diluent across the sensors giving you an almost instant validation.

I must admit I am not sure about this. I have heard that ADV's sometimes malfunction and that it is common to have a valve which enables the diver to stop the ADV working should it start putting air into the loop unecessarily.

Trouble is, I simply do not have enough knowledge at this stage to know whether this is a neat and minimalist design feature or something which could cause problems. I am probably misunderstanding something here.

What do you all think? Should I be concerned?

As Andy explained i would not consider this a problem, the Kiss's also work this way. The only mCCR i know of that comes with a dill addition is the rEvo. Having a manual addition is a nice feature that you can add to the pelagian without any major problem.

/Jonny

wearypanda · 20th February 2007, 21:28

Quote: (Originally Posted by Rebreatherlab)

The loop is purged as follows;

1. Roll on your back, (horizontal facing the surface).
2. Pull the dumpvalve on the exhale counter lung and the ADV will purge and stop when you relese the dump cord. Cross your arms if you want to reduce the flexible part of the loop to conserve gas.

If you want a secondary input for DIL to the loop, just buy a dry suit inflator valve from Apex, cut a hole in the inhale CL and connect the feed hose to your bail out or on board DIL.

OR

Order the up coming BOV lower section, connect to the present DSV and ad Dil to the loop by taking a breath from the OC BOV and exahle in to the loop.

If you want to ad a inline on/off switch for the ADV you might want to wait until we provide one as we will make one that connects direct from the 1st stage for easy reach. If the ADV freeflows and freeze in the open position you would with out the on off switch simply close the dil cylinder valve and wait a few minutes. It will not likely stay frozen for long with the warm loop gas surrounding the lever mechanism. If in the same time need to purge the loop due to high PO2, it will be very easy! If you need to momentarily ad some DIL to your wing, then feather the valve while inflating the wing and shut down the valve after. You might also want to consider routing the wing inflation hose to your bail out.

Cheers,

Andy

Just as I thought. My understamding and knowledge is the limiting factor here. Sounds like it is a non-issue. This does not surprise me at all!

19th February 2007, 19:56	#1 (permalink)
wearypanda New Member Current Rebreather/s: Pelagian Other Rebreather/s: Inspiration Classic Pelagian Join Date: Oct 2006 Location: Wiltshire, UK Posts: 93	Pelagian -is this the right choice? Having decided to go the mCCR route I eventually narrowed my choice down to either the COPIS Meg or the Pelagian. After spending many hours reading (mainly here, asking questions and thinking a lot about which CCR is the right choice for me, I have pretty much decided that the Pelagian is the right unit for me. The Pelagian has quite a few attributes and features which I feel give it an edge. These include:= Diluent injection designed to blow condensation off sensors and give almost instant sensor validation Compact size Needle valve controlled O2 metering Uses lots of OC parts making it a lot easier to fix problems without having to order parts frommanufacturer Low volume head and designed so that cylinders have valves at top make for better trim The Pelagian is cheaper than the COPIS but this is certainly not the most important factor. The downsides to the Pelagian all stem from the fact that it is a new unit and it is made in Thailand. So, currently there are very few instructors (training has to be done in Thailand - what a hardship!) and manufacturer's support is a relatively unknown quantity. I am also a little concerned that there might be design flaws yet to reveal themselves as the unit becomes more extensive used. I would greatly appreciate any advice or thoughts you may have on this choice before I finally part with my hard earned cash. Thanks in advance.
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19th February 2007, 20:52	#2 (permalink)
diverklondike Just one of the Peasants Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Inspiration Classic Other CCR Join Date: Oct 2005 Location: Delaware, USA Posts: 1,610	Re: Pelagian -is this the right choice? Quote: (Originally Posted by wearypanda) Having decided to go the mCCR route I eventually narrowed my choice down to either the COPIS Meg or the Pelagian. After spending many hours reading (mainly here, asking questions and thinking a lot about which CCR is the right choice for me, I have pretty much decided that the Pelagian is the right unit for me. The Pelagian has quite a few attributes and features which I feel give it an edge. These include:= Diluent injection designed to blow condensation off sensors and give almost instant sensor validation Compact size Needle valve controlled O2 metering Uses lots of OC parts making it a lot easier to fix problems without having to order parts frommanufacturer Low volume head and designed so that cylinders have valves at top make for better trim The Pelagian is cheaper than the COPIS but this is certainly not the most important factor. The downsides to the Pelagian all stem from the fact that it is a new unit and it is made in Thailand. So, currently there are very few instructors (training has to be done in Thailand - what a hardship!) and manufacturer's support is a relatively unknown quantity. I am also a little concerned that there might be design flaws yet to reveal themselves as the unit becomes more extensive used. I would greatly appreciate any advice or thoughts you may have on this choice before I finally part with my hard earned cash. Thanks in advance. While I do not own a Meg, here are a couple points to consider... All of your down sides are significant ones... The Meg has been dove to many extremes and done well... 1) If you feel the Copis Meg is a little larger than you want, I would expect that Leon would sell you a Mini-Copis Meg. Ron M... Can you confirm this?? 2) If you wanted I am sure that you could invert the bottles on the Meg. I have seen a few people doing this... 3) The ability to blow dil accross the sensor face is a nice to have but my experiance is that this has not been an issue for the Meg as it applies to condensation. Note that cell technology has improved quite a bit over the years in it's ability to handle condensation. Two other last items... You can upgrade a Copis it to a full ECCR... The Meg has an excellent resale value if you were to choose to sell it... Good Luck and Dive Safe! Mark
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19th February 2007, 21:41	#3 (permalink)
dave t Custom Title Allowed! Current Rebreather/s: Inspiration Classic Inspiration Vision Evolution Sport Kiss Classic Kiss Dolphin Ray Azimuth Home Build Other Rebreather/s: Dolphin Ray Azimuth Home Build Join Date: May 2005 Location: UK Posts: 654	Re: Pelagian -is this the right choice? Depending on how the pelagian blows gas over the sensors can be a plus or a minus. Directing a stream of gas directly onto the cell face can be detrimental to the cells health. Was ok when the cis-luner first used that trick as the cells then had a gause face which was more robust, but now with the ptfe faced cells they are a bit delicate looks like a nice unit though well thought out! Dave
(Offline)

20th February 2007, 05:26	#4 (permalink)
silent running Mature mouth breather Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Jun 2005 Location: U.S.A. Brooklyn, New York Posts: 1,832	Re: Pelagian -is this the right choice? Quote: (Originally Posted by wearypanda) Having decided to go the mCCR route I eventually narrowed my choice down to either the COPIS Meg or the Pelagian. After spending many hours reading (mainly here, asking questions and thinking a lot about which CCR is the right choice for me, I have pretty much decided that the Pelagian is the right unit for me. The Pelagian has quite a few attributes and features which I feel give it an edge. These include:= Diluent injection designed to blow condensation off sensors and give almost instant sensor validation Compact size Needle valve controlled O2 metering Uses lots of OC parts making it a lot easier to fix problems without having to order parts frommanufacturer Low volume head and designed so that cylinders have valves at top make for better trim The Pelagian is cheaper than the COPIS but this is certainly not the most important factor. The downsides to the Pelagian all stem from the fact that it is a new unit and it is made in Thailand. So, currently there are very few instructors (training has to be done in Thailand - what a hardship!) and manufacturer's support is a relatively unknown quantity. I am also a little concerned that there might be design flaws yet to reveal themselves as the unit becomes more extensive used. I would greatly appreciate any advice or thoughts you may have on this choice before I finally part with my hard earned cash. Thanks in advance. Hello wp, what Dave said about sensor faces being a bit fragile is my understanding as well. So unless the unit has some kind of restrictor to really limit the dil flow, I don't think it's a very good idea to blow dil directly at the sensor faces. I would also wonder about the effect of the difference btw the warm loop temp and the fresh, possibly very cold gas hitting the sensor face... Otherwise, the Pelagian looks well thought out. I wonder how the under-arm CLs breathe compared to standard OTS CLs? The inner bladder CL idea seems like a good idea for durability and resistance to punctures/snags. And I wonder if the Pelagian will ever have a radial scrubber. You can buy radials aftermarket for the Meg. I can't tell how the sensors are wired, if they're KISS like independent circuits for the 2 sensor display and where the battery is located, but the idea of having the 3rd sensor going to a computer seems like a good one. And I'm guessing that the COPIS Meg has a HUD and the Pelagian does not. I think every unit should have a HUD. But the Pelagian has the needle valve and from my indirect experience diving with a friend of mine and his buddies who use needle valved Dolphins, it seemed like the way to go for MCCR. They would adjust the flow once or twice during the dive and never had to hit the add button. It worked well for high and low workloads and the needle valve itself was easy to clean. Tough choice, lots of things to think about but it seems like you'd need more info about the Pelagian to make a good choice... -Andy
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20th February 2007, 08:43	#5 (permalink)
rogeringebo Custom Title Allowed! Current Rebreather/s: Pelagian Other Rebreather/s: Megalodon Classic Kiss Pelagian Join Date: Sep 2005 Location: Stockholm Sweden Posts: 699	Re: Pelagian -is this the right choice? Quote: (Originally Posted by diverklondike) While I do not own a Meg, here are a couple points to consider... All of your down sides are significant ones... The Meg has been dove to many extremes and done well... 1) If you feel the Copis Meg is a little larger than you want, I would expect that Leon would sell you a Mini-Copis Meg. Ron M... Can you confirm this?? 2) If you wanted I am sure that you could invert the bottles on the Meg. I have seen a few people doing this... 3) The ability to blow dil accross the sensor face is a nice to have but my experiance is that this has not been an issue for the Meg as it applies to condensation. Note that cell technology has improved quite a bit over the years in it's ability to handle condensation. Two other last items... You can upgrade a Copis it to a full ECCR... The Meg has an excellent resale value if you were to choose to sell it... Good Luck and Dive Safe! Mark Hi Guys! Here is my view on the matter.. I own and dive both a Megalodon with solenoid and a Pelagian. I work as a diveinstructor and dive rebreathers almost every day. I started diving a KISS because I like the idea of controlling my O2 flow myself without electronics. After testing the Pelagian prototype I ordered one straight away and sold my KISS. While waiting for my Pelagian I bought and dived my Meg with much joy. I always dive it manual with the electronics set below the setpoint I choose to dive,like a parashute sort of. I still have my Meg and I think it is the best ECCR on the market but prefer my Pelagian because -Its much more compact -Lighter -It can be taken on a airplane as carry on, I think it is the lightest rebreather on the market that is made for serious deep dives. -Its made so you can put on any tanks available,all you need is a piece of webbing (or a weightbelt) and the put on what ever is available on the boat,island or resort you are. No need for Tigermounts or ratteling G-snaps with hoseclamps that turn out to be to short. I have even dived with 12 liter tanks (80cf) -Better trim because airspace in head is kept to a minimum to avoid vertical trim. Meg have a huge metal tube with lots of unneccesray air in it which mean more lead on you hips. Pelagian is built for having tankvalves/regs up so trim will improve and no need for weights high up to be horizontal. I dive my Meg the same way btw -Easier to take apart and handle. -Hold setpoint much better -Much bigger scrubber (about 3,5kg of Sofnolime) -Curved lungs that stay out of your way -Will be possible to order with supercompact BOV soon. Smallest on the market but with the biggest inner bore for good weight of breathing. -You can plug in Vr3 or HS Explorer on third cell for complete redundant readout (I dive like this) -Sensor validation via ADV,breath out a half breath through nose and inhale slowly,ADV will kick in a blow DIL over cells and you see straight away which cell is off...no need for complete flush and loss of gas. The gas blow in an angle across the cell and not straight on the membrane. Its maine objective is to help you check which cell or cells are off. The loss of condensation is just a nice bonus. -No theorethical depth limit You are right,there are no electronic kit you can buy for it at the moment but Andy dont want electronics handeling your O2 feed,Thats the whole idea with the Pelagian. No HUD,no solenoid,no voting,no computer deciding whats best for you. You have to decide for yourself which means no nasty surprises with stuck electronics feeding O2 at the wrong time or morse code blinking HUD that might jam or show wrong colour (if you even can see the difference in tropical waters? I can not) Iam quite sure that you could fit Hammerhead or Shearwater electronics to your Pelagian if you want to. I hope this helps to clarify some things. Dive safe! Roger Ingebo PADI MSDT KISS diver Megalodon diver Pelagian instructor
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20th February 2007, 10:46	#6 (permalink)
Rebreatherlab RebreatherWorld Sponsor Current Rebreather/s: Pelagian Other Rebreather/s: Not Bought Yet Classic Kiss Pelagian Join Date: Sep 2005 Location: Thailand Posts: 202	Re: Pelagian -is this the right choice? Very true. Cis Lunar MK5P feeds DIL through a tight nozzle straight to the cell membranes. Many divers have tried the current Teledyne R17D cells, but usually get problems with cells going way off for a week after diving due to the standard hydrophobic membrane. To address this issue we have fed the Dil through a 5,5 mm bore from a 40 degree angle. The speed of the gas flow is controlled by the diver as it is triggered from the ADV, i.e. you dump half a breath from your nose and inhale slowly. As long as you hear the ADV hissing the DIL is displacing the surrounding gas and you can work out what is realistic. Typically the PO2 will read slightly higher than DIL PO2 due to the tiny influence of the surrounding gas, flow of gas etc. Theoretically also the temperature difference will have a small effect. As the idea is to get a quick reality check a few times during a dive, or at any time the two readouts disagree, it is of minor importance. To give a practical example: with air dil the read out may show appox Po2 1,1 at 40 msw instead of the mathematically correct 1,045. To test the long term effect, the first prototype was dived for one year with out any problems. The prototype used a smaller bore feed nozzle and inflator style feed actuator, so the speed of the gas flow was faster and more difficult to control than what we have now with the ADV and divers lungs being the actuator. The wiring is as follows: Molex connector to wire, soldered, epoxy sealed and heat shrinked. Wire to battery compartment with epoxy seal, battery compartment to external gland, (with expoxy sealed plastic internal body). External cable jacket is gas sealed on both ends and carries signal for both cells and battery cable to the shared display housing. PCB and all componenets are sealed and will survive a flood in seawater. All componenents will survive inveresed poplarity and if plus and minus is shorted only the PCB plus trace will fry. This can be fixed quite easily. To prevent a short the battery is kept in its own sealed compartment. To test the integrity of the seals we pressurize the loop to 4 bar with the calibration plug to the display housing open. Any minor leak after a few minutes would be visible on the PO2 read outs. The motto while designing the head and all other parts was to provide a very compact and light weight CCR to the travelling diver that did not compromise on duration, WOB and flexibility. It took 6 months to design the head and I feel that we have reached what we set out to do. As the main internal diameter of the scrubber is 126, 8 mm, I don't think we will be focusing on a radial scrubber. Personally I also dive a Cis MK5P which has a radial can and I always get more milage out of the Pelagian standard axial scrubber and a lot less abrupt CO2 break through if pushed to the limit. WOB is significantly lower on the Pelagian than on the CIS and many other current units so why radial when the present axial works fine? We are currently working on UK marketing so hopefully it will not be long until people can see and try the units with out having to come for a nice training holiday to Thailand! Best, Andy REBREATHER LAB Quote: (Originally Posted by dave t) Depending on how the pelagian blows gas over the sensors can be a plus or a minus. Directing a stream of gas directly onto the cell face can be detrimental to the cells health. Was ok when the cis-luner first used that trick as the cells then had a gause face which was more robust, but now with the ptfe faced cells they are a bit delicate looks like a nice unit though well thought out! Dave
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20th February 2007, 20:10	#7 (permalink)
wearypanda New Member Current Rebreather/s: Pelagian Other Rebreather/s: Inspiration Classic Pelagian Join Date: Oct 2006 Location: Wiltshire, UK Posts: 93	Re: Pelagian -is this the right choice? Thanks so much everyone who responded. One design aspect that I was not aware of until today is that on the Pelagian Diluent can only be added to the loop through the ADV. This means (I think) that to do a diluent flush or indeed any addition of diluent it is necessary to vent air from the loop by breathing into the mask and your next breath will draw diluent into the loop through the ADV. It is the ADV which blows diluent across the sensors giving you an almost instant validation. I must admit I am not sure about this. I have heard that ADV's sometimes malfunction and that it is common to have a valve which enables the diver to stop the ADV working should it start putting air into the loop unecessarily. Trouble is, I simply do not have enough knowledge at this stage to know whether this is a neat and minimalist design feature or something which could cause problems. I am probably misunderstanding something here. What do you all think? Should I be concerned?
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20th February 2007, 20:45	#8 (permalink)
Rebreatherlab RebreatherWorld Sponsor Current Rebreather/s: Pelagian Other Rebreather/s: Not Bought Yet Classic Kiss Pelagian Join Date: Sep 2005 Location: Thailand Posts: 202	Re: Pelagian -is this the right choice? The loop is purged as follows; 1. Roll on your back, (horizontal facing the surface). 2. Pull the dumpvalve on the exhale counter lung and the ADV will purge and stop when you relese the dump cord. Cross your arms if you want to reduce the flexible part of the loop to conserve gas. If you want a secondary input for DIL to the loop, just buy a dry suit inflator valve from Apex, cut a hole in the inhale CL and connect the feed hose to your bail out or on board DIL. OR Order the up coming BOV lower section, connect to the present DSV and ad Dil to the loop by taking a breath from the OC BOV and exahle in to the loop. If you want to ad a inline on/off switch for the ADV you might want to wait until we provide one as we will make one that connects direct from the 1st stage for easy reach. If the ADV freeflows and freeze in the open position you would with out the on off switch simply close the dil cylinder valve and wait a few minutes. It will not likely stay frozen for long with the warm loop gas surrounding the lever mechanism. If in the same time need to purge the loop due to high PO2, it will be very easy! If you need to momentarily ad some DIL to your wing, then feather the valve while inflating the wing and shut down the valve after. You might also want to consider routing the wing inflation hose to your bail out. Cheers, Andy Quote: (Originally Posted by wearypanda) Thanks so much everyone who responded. One design aspect that I was not aware of until today is that on the Pelagian Diluent can only be added to the loop through the ADV. This means (I think) that to do a diluent flush or indeed any addition of diluent it is necessary to vent air from the loop by breathing into the mask and your next breath will draw diluent into the loop through the ADV. It is the ADV which blows diluent across the sensors giving you an almost instant validation. I must admit I am not sure about this. I have heard that ADV's sometimes malfunction and that it is common to have a valve which enables the diver to stop the ADV working should it start putting air into the loop unecessarily. Trouble is, I simply do not have enough knowledge at this stage to know whether this is a neat and minimalist design feature or something which could cause problems. I am probably misunderstanding something here. What do you all think? Should I be concerned?
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20th February 2007, 21:02	#9 (permalink)
JonnyB Johnny The Hatch Current Rebreather/s: MK 15.X Titan Other CCR Other SCR Home Build Other Rebreather/s: Not Bought Yet Inspiration Classic Megalodon Sport Kiss Classic Kiss Other CCR Other SCR Home Build Join Date: Jan 2005 Location: Sweden (Stockholm)/Cyprus(Ayia Napa) Posts: 970	Re: Pelagian -is this the right choice? Quote: (Originally Posted by wearypanda) Thanks so much everyone who responded. One design aspect that I was not aware of until today is that on the Pelagian Diluent can only be added to the loop through the ADV. This means (I think) that to do a diluent flush or indeed any addition of diluent it is necessary to vent air from the loop by breathing into the mask and your next breath will draw diluent into the loop through the ADV. It is the ADV which blows diluent across the sensors giving you an almost instant validation. I must admit I am not sure about this. I have heard that ADV's sometimes malfunction and that it is common to have a valve which enables the diver to stop the ADV working should it start putting air into the loop unecessarily. Trouble is, I simply do not have enough knowledge at this stage to know whether this is a neat and minimalist design feature or something which could cause problems. I am probably misunderstanding something here. What do you all think? Should I be concerned? As Andy explained i would not consider this a problem, the Kiss's also work this way. The only mCCR i know of that comes with a dill addition is the rEvo. Having a manual addition is a nice feature that you can add to the pelagian without any major problem. /Jonny __________________ A quote from Crazyduck - In remembering our own Rob Davies. "Outbound flight 777 heavy you are cleared for flight Due west into that warm red Texas sunset You have angels on your wings and divers memories on your six." Rest In Peace http://www.divetekcyprus.com http://www.diveccr.com
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20th February 2007, 21:28	#10 (permalink)
wearypanda New Member Current Rebreather/s: Pelagian Other Rebreather/s: Inspiration Classic Pelagian Join Date: Oct 2006 Location: Wiltshire, UK Posts: 93	Re: Pelagian -is this the right choice? Quote: (Originally Posted by Rebreatherlab) The loop is purged as follows; 1. Roll on your back, (horizontal facing the surface). 2. Pull the dumpvalve on the exhale counter lung and the ADV will purge and stop when you relese the dump cord. Cross your arms if you want to reduce the flexible part of the loop to conserve gas. If you want a secondary input for DIL to the loop, just buy a dry suit inflator valve from Apex, cut a hole in the inhale CL and connect the feed hose to your bail out or on board DIL. OR Order the up coming BOV lower section, connect to the present DSV and ad Dil to the loop by taking a breath from the OC BOV and exahle in to the loop. If you want to ad a inline on/off switch for the ADV you might want to wait until we provide one as we will make one that connects direct from the 1st stage for easy reach. If the ADV freeflows and freeze in the open position you would with out the on off switch simply close the dil cylinder valve and wait a few minutes. It will not likely stay frozen for long with the warm loop gas surrounding the lever mechanism. If in the same time need to purge the loop due to high PO2, it will be very easy! If you need to momentarily ad some DIL to your wing, then feather the valve while inflating the wing and shut down the valve after. You might also want to consider routing the wing inflation hose to your bail out. Cheers, Andy Just as I thought. My understamding and knowledge is the limiting factor here. Sounds like it is a non-issue. This does not surprise me at all!
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