Prism Scrubber etc

mverick · 27th January 2007, 22:22

Quote: (Originally Posted by Shas)

As the manufacturer I can assure you that the SMI sensors are proprietary and built under license for us and sold exclusively through us and our agents. The electronics were designed to match the sensors.

The secondary is also matched and the comment on watching the needle movement refers to when the meter is connected and reading a specific sensor - what you see is the needle movement matching the rise in mV output from the sensor and showing that reading - as sensors age the time to reach its output increases (especially for high PO2s as in calibration) and the lag between sensor response is evident to trained users.

The decision to use plastics was made as discussed in the scrubber article here - http://www.rebreatherworld.com/closed-circuit-rebreather-articles/6486-smi-scrubber.html.

WOB, weight and duration, along with tight and accurate electronic setpoint control was the overriding goal. The analog secondary gives us a completely power free option to verify function - the trade off is that you need to treat it like a camera or video - most customers try not to drop or throw their units around and for every one of the vocal individuals who were unable to work with that we have three who would have it no other way.

Bottom line - you do your research as the user and you chose based on what's important for you. Please bear in mind some of the people who post have vested interests - I do, and I'm tired of seeing people who have an axe to grind or grudge against us posting snide digs and BS which they can't substantiate or half truths which gloss over their part in it.

Best Wishes,
Shas

Thank you for that. As long as you tell people it's delicate that is fine. When I asked about the unit. That was not what I was told. I was told it was very tough. Never a mention about the secondary needing attention.

I tend to drop my dive gear. Dropped my Halcyon 10hid. New bulb needed but I had one. My Salvo I don't have that problem with. And it was an accident. I clipped it off but when removing it the boat shifted and to the floor it went. Not a lot I could do. About 8ft seas. 3 sets of duals got thrown off the bench. Storm came up fast and guy's were new to boat diving in Great Lakes so there gear wasn't restrained well. One set almost went off the boat.

So, I require more robust cause sooner or later, I'm gonna drop it.

Drmike · 28th January 2007, 05:56

The SMI cells are very good. I never had any issue with them - the only reasons I switched to RD10s was they fit better in the MK15.5 (SMI cells need o-ring to fit) plus I MUCH preffer hard soldered cells (in a MK15.5 as you can fully seal the wire/connection so no need to worry about moisture getting in and causing wire corrosion) that I cant do with the pin connectors on the SMI cells.

To me there are far more things to go wrong in a mechanical analog gauge than in a digital one.

A digital one either works or it doesnt. Analogs can stick or can have hysterisis.

I have had analogs seemingly working fine but actually showing me slightl;y higher (incorrect) ppo2 on ALL cells (due to hysterisis in the gauge) ...thats not good from a deco perspective! I dont know if that is possible/less likely with the latest SMI analogs - I know they are supposed to be sturdier.

DaveC · 29th January 2007, 00:32

Well, so far my analog is working just fine. Yes I've dropped it a couple times as I'm human and no human is perfect. When its not in use I have a small pelican case that it sits in. If I'm on a boat, where there are people I don't know, I put it in the case. Just in case someone get clumbsy and knocks it about. Would a digital be better, maybe. Would I like a digital, sure. Sharon, any word on the SMI digitals? I'm very happy with my Prism. Some like it, some don't. Oh well.

NEwreckdiver · 29th January 2007, 13:43

Quote: (Originally Posted by reefrat)

Anyway, the scrubber. What's with the locking mechanism where it attaches to the head (the whole thing looks like deluxe tupperware), is it REALLY secure and tough?

The scrubber is seated against a gasket in the head and held there by a spring at the bottom of the bucket. As long as you invert the rig as you lock down the bucket, the scrubber basket will easily seal against this gasket and lock into place being supported by the spring. Invert, shake and then lock down/twist the bucket. Very easy and very secure.

Quote: (Originally Posted by reefrat)

And the secondary analogue handset, when your checking that is it a PITA to select all the sensors separately?

No. I do admit that it would be nice to see all 3 at once. But I have found having to scroll through the 3 sensors forces me to stop what I am doing and really take a look at what's going on and really verify as opposed to skimming, which is something you get used to doing if you spend enough time on these chat boards.

Quote: (Originally Posted by reefrat)

Lastly, the proprietary sensors- is this an issue as opposed to most other units on the the market that use the more commonly available Teledyne units and can others be used in the unlikely event that something ever happens to SMI?

I am sure you can find something else that will work, but regardless if SMI is trying to make money off of these things (that's ok, right? They are a business...), the sensors are meant to be used with this rig and it's electronics. If that's so hard to take, then it might be a showstopper for you. It wasn't for us.

Quote: (Originally Posted by reefrat)

Don't get me wrong, I've read a lot about the Prism- seen it dived once and so far it's a very attractive option, these are the only (maybe) potential issues with it that I can see!

No rebreather is perfect. The PRISM isn't perfect. Part of the issues with any rebreather are related to the learning curve of being new with it. Yes there are some fragile parts (like the secondary). But if you are responsible with your equipment and take care of it, then you'll do fine. Yes, shit happens. One time I forgot to bungee in my tanks on a bench and they fell over --- sheared both my first stages off at the DIN fittings. Whose fault was that? The reg manufacturer because they didn't use stainless steel stems? No it was mine because I was thinking about hot chocolate and not tank bungees.

Cheers,
Heather Knowles

mverick · 29th January 2007, 15:29

Quote: (Originally Posted by NEwreckdiver)

Yes, shit happens. One time I forgot to bungee in my tanks on a bench and they fell over --- sheared both my first stages off at the DIN fittings. Whose fault was that? The reg manufacturer because they didn't use stainless steel stems? No it was mine because I was thinking about hot chocolate and not tank bungees.

Cheers,
Heather Knowles

Stainless steel is soft. You'd want something else.

But, then where do you want it to break you have to ask yourself.

NEwreckdiver · 29th January 2007, 19:47

Quote: (Originally Posted by mverick)

Stainless steel is soft. You'd want something else.

But, then where do you want it to break you have to ask yourself.

That really wasn't my point, but ok. And since it wasn't my boat I would have preferred that tanks plunged through the deck leaving my whole rig intact, but yes it was ultimately preferable that the regs failed there as opposed to somewhere else.

My point was that if you take care of your things you'll avoid most damage, even if the parts are "fragile". And sometimes you just can't avoid it. I dove the Empress of Ireland from a RIB this past year with my PRISM. I had to take all the gear off in the water, then watch my precious toy get dragged up over the side and down into the hull. No problems, nothing broken. In years past I've dove with my OC gear from this very same RIB and smashed up all kinds of stuff. So go figure.

Cheers
HK

27th January 2007, 22:22	#21 (permalink)
mverick ScubaPimp Current Rebreather/s: Megalodon Other CCR Home Build Other Rebreather/s: Other CCR Home Build Join Date: Aug 2005 Posts: 541	Re: Prism Scrubber etc Quote: (Originally Posted by Shas) As the manufacturer I can assure you that the SMI sensors are proprietary and built under license for us and sold exclusively through us and our agents. The electronics were designed to match the sensors. The secondary is also matched and the comment on watching the needle movement refers to when the meter is connected and reading a specific sensor - what you see is the needle movement matching the rise in mV output from the sensor and showing that reading - as sensors age the time to reach its output increases (especially for high PO2s as in calibration) and the lag between sensor response is evident to trained users. The decision to use plastics was made as discussed in the scrubber article here - http://www.rebreatherworld.com/closed-circuit-rebreather-articles/6486-smi-scrubber.html. WOB, weight and duration, along with tight and accurate electronic setpoint control was the overriding goal. The analog secondary gives us a completely power free option to verify function - the trade off is that you need to treat it like a camera or video - most customers try not to drop or throw their units around and for every one of the vocal individuals who were unable to work with that we have three who would have it no other way. Bottom line - you do your research as the user and you chose based on what's important for you. Please bear in mind some of the people who post have vested interests - I do, and I'm tired of seeing people who have an axe to grind or grudge against us posting snide digs and BS which they can't substantiate or half truths which gloss over their part in it. Best Wishes, Shas Thank you for that. As long as you tell people it's delicate that is fine. When I asked about the unit. That was not what I was told. I was told it was very tough. Never a mention about the secondary needing attention. I tend to drop my dive gear. Dropped my Halcyon 10hid. New bulb needed but I had one. My Salvo I don't have that problem with. And it was an accident. I clipped it off but when removing it the boat shifted and to the floor it went. Not a lot I could do. About 8ft seas. 3 sets of duals got thrown off the bench. Storm came up fast and guy's were new to boat diving in Great Lakes so there gear wasn't restrained well. One set almost went off the boat. So, I require more robust cause sooner or later, I'm gonna drop it.
(Offline)

28th January 2007, 05:56	#22 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,300	Re: Prism Scrubber etc The SMI cells are very good. I never had any issue with them - the only reasons I switched to RD10s was they fit better in the MK15.5 (SMI cells need o-ring to fit) plus I MUCH preffer hard soldered cells (in a MK15.5 as you can fully seal the wire/connection so no need to worry about moisture getting in and causing wire corrosion) that I cant do with the pin connectors on the SMI cells. To me there are far more things to go wrong in a mechanical analog gauge than in a digital one. A digital one either works or it doesnt. Analogs can stick or can have hysterisis. I have had analogs seemingly working fine but actually showing me slightl;y higher (incorrect) ppo2 on ALL cells (due to hysterisis in the gauge) ...thats not good from a deco perspective! I dont know if that is possible/less likely with the latest SMI analogs - I know they are supposed to be sturdier. __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment
(Offline)

29th January 2007, 00:32	#23 (permalink)
DaveC New Member Current Rebreather/s: Sport Kiss Classic Kiss Other Rebreather/s: Prism Topaz Join Date: Mar 2005 Location: Ontario. Canada Posts: 192	Re: Prism Scrubber etc Well, so far my analog is working just fine. Yes I've dropped it a couple times as I'm human and no human is perfect. When its not in use I have a small pelican case that it sits in. If I'm on a boat, where there are people I don't know, I put it in the case. Just in case someone get clumbsy and knocks it about. Would a digital be better, maybe. Would I like a digital, sure. Sharon, any word on the SMI digitals? I'm very happy with my Prism. Some like it, some don't. Oh well. __________________ Dave Any day in the water is better then any day in the office.
(Offline)

29th January 2007, 13:43	#24 (permalink)
NEwreckdiver New Member Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Oct 2005 Location: Boston MA Posts: 49	Re: Prism Scrubber etc Quote: (Originally Posted by reefrat) Anyway, the scrubber. What's with the locking mechanism where it attaches to the head (the whole thing looks like deluxe tupperware), is it REALLY secure and tough? The scrubber is seated against a gasket in the head and held there by a spring at the bottom of the bucket. As long as you invert the rig as you lock down the bucket, the scrubber basket will easily seal against this gasket and lock into place being supported by the spring. Invert, shake and then lock down/twist the bucket. Very easy and very secure. Quote: (Originally Posted by reefrat) And the secondary analogue handset, when your checking that is it a PITA to select all the sensors separately? No. I do admit that it would be nice to see all 3 at once. But I have found having to scroll through the 3 sensors forces me to stop what I am doing and really take a look at what's going on and really verify as opposed to skimming, which is something you get used to doing if you spend enough time on these chat boards. Quote: (Originally Posted by reefrat) Lastly, the proprietary sensors- is this an issue as opposed to most other units on the the market that use the more commonly available Teledyne units and can others be used in the unlikely event that something ever happens to SMI? I am sure you can find something else that will work, but regardless if SMI is trying to make money off of these things (that's ok, right? They are a business...), the sensors are meant to be used with this rig and it's electronics. If that's so hard to take, then it might be a showstopper for you. It wasn't for us. Quote: (Originally Posted by reefrat) Don't get me wrong, I've read a lot about the Prism- seen it dived once and so far it's a very attractive option, these are the only (maybe) potential issues with it that I can see! No rebreather is perfect. The PRISM isn't perfect. Part of the issues with any rebreather are related to the learning curve of being new with it. Yes there are some fragile parts (like the secondary). But if you are responsible with your equipment and take care of it, then you'll do fine. Yes, shit happens. One time I forgot to bungee in my tanks on a bench and they fell over --- sheared both my first stages off at the DIN fittings. Whose fault was that? The reg manufacturer because they didn't use stainless steel stems? No it was mine because I was thinking about hot chocolate and not tank bungees. Cheers, Heather Knowles
(Offline)

29th January 2007, 15:29	#25 (permalink)
mverick ScubaPimp Current Rebreather/s: Megalodon Other CCR Home Build Other Rebreather/s: Other CCR Home Build Join Date: Aug 2005 Posts: 541	Re: Prism Scrubber etc Quote: (Originally Posted by NEwreckdiver) Yes, shit happens. One time I forgot to bungee in my tanks on a bench and they fell over --- sheared both my first stages off at the DIN fittings. Whose fault was that? The reg manufacturer because they didn't use stainless steel stems? No it was mine because I was thinking about hot chocolate and not tank bungees. Cheers, Heather Knowles Stainless steel is soft. You'd want something else. But, then where do you want it to break you have to ask yourself.
(Offline)

29th January 2007, 19:47	#26 (permalink)
NEwreckdiver New Member Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Oct 2005 Location: Boston MA Posts: 49	Re: Prism Scrubber etc Quote: (Originally Posted by mverick) Stainless steel is soft. You'd want something else. But, then where do you want it to break you have to ask yourself. That really wasn't my point, but ok. And since it wasn't my boat I would have preferred that tanks plunged through the deck leaving my whole rig intact, but yes it was ultimately preferable that the regs failed there as opposed to somewhere else. My point was that if you take care of your things you'll avoid most damage, even if the parts are "fragile". And sometimes you just can't avoid it. I dove the Empress of Ireland from a RIB this past year with my PRISM. I had to take all the gear off in the water, then watch my precious toy get dragged up over the side and down into the hull. No problems, nothing broken. In years past I've dove with my OC gear from this very same RIB and smashed up all kinds of stuff. So go figure. Cheers HK
(Offline)

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode