Membrane Nitrox system

[Mooring Inspector]

I am just about to purchase a NUVAIR LP560 Membrane system,is there anything that I should know about before I buy it ? Also has anyone had any experience with " The Blue Solution" Filter system by Michael Salzer ?

 

[rcontrera]

I can't help you with the filter, but the LP560 is a beautiful machine!! I just finished a new installation of the LP280 which is the smaller version that only handle 10 CFM to 40% instead of 20 CFM to 40% like yours. You must have a HUGE compressor!

A couple things to note.
The LP air dryer is a refrigeration unit so will not blow off like your HP compressor does. It will drip instead so check your drains regularly to avoid a puddle on the floor.

Changing oil is a long term thing (about 1500 to 2000 hours) but requires moving out the machine to access the back panel. It isn't a hard job removing the back panel, but you have to remember to install it somewhere that gives you plenty of room to get behind it when the time comes.

Have you ordered your machine yet? If you haven't, drop me a line and I will see what I can do to get you the best price.

 

[Mooring Inspector]

Hi Ray
Thanks for the info, I will probably go for the 26hp compressor for this system. At that sort of interval, I dont have a problem removing the back panel.
I was going to see if they have a special Beneath the Sea discount at the show.
What sort of price could you get the same set-up fo me? with options and Tri-mix capability too. Let me know.
Regards
Mooring Inspector.

 

[rcontrera]

I guess I need to back up and ask ... what compressor are you going to match the LP560 with?

If you have a 26 CFM (HP doesn't really matter) compressor then the LP560 will only get you about 36% at full flow. The LP560 will get you up to 40% only on a compressor that puts out 20 CFM or less. If you only need 32%, then it can be matched to a compressor that pumps up to 36 CFM.

Let me try this ... capacities of the Nitrox Generators are:
LP280 ... 40%- 6-10 CFM; 32%- 6-18 CFM
LP420 ... 40%-11-16 CFM; 32%- 11-32 CFM
LP560 ... 40%-10-20 CFM; 32%- 10-36 CFM
LP713 ... 40%-20-25 CFM; 32%- 20-45 CFM

Remember, these machines are only designed to manufacture Nitrox. Doing trimix is a specialized custom design that will actually happen after the generator.

I don't know what David is taking with him to the show, but he likes to sell what he has on the floor so he can just walk away afterwards. If you bring a pallet jack and a truck, he just might make you a deal. Make sure that you let him know that you started working with me. As a bare minimum, you would save on shipping time.

 

[rcontrera]

Well, as you found out, David only took the personal sized compressors and the diving equipment line but left the big machines at the office.

If you are still looking, PM me or drop me a line at ray@rayzplace.com and I can get you set up. I don't have the Nitrox Generators up yet on the Nitrox pages of the website but hope to by the weekend. Sorry

 

[Scuba Duck]

You might consider why you are purchasing a Nitrox system and what would be the best solution. No question about it, the Nuvair systems are beautiful machines. They also cost a lot of money. If your primary reason for obtaining a Nitrox system is to sell Nitrox fills at reasonable prices, you should look into what it will cost you to actually fill a tank. You might also consider the other options of partial pressure blending or continuous gas blending as alternatives that might be more cost effective depending on the quantity of nitrox you plan on filling. If you buy a $20,000 Nitrox system from Nuvair, what do you have to charge per tank to recover that? What about the other costs associated with electricity and labor?

Check out this link, fill in dollar amounts that are relevent to your Dive Shop, and see what it might really cost you to fill Nitrox Tanks.

http://www.nitroxmadeeasy.com/Documents/NitroxCostBreakdown.xls

http://www.nitroxmadeeasy.com/Methods.htm

If the Nuvair system makes the most sense for you, or if you don't want to deal with bottled oxygen, then by all means, drop the cash and buy the Nuvair system.

 

[KOMPRESSOR]

I can't help you with the filter, but the LP560 is a beautiful machine!! I just finished a new installation of the LP280 which is the smaller version that only handle 10 CFM to 40% instead of 20 CFM to 40% like yours. You must have a HUGE compressor!

A couple things to note.
The LP air dryer is a refrigeration unit so will not blow off like your HP compressor does. It will drip instead so check your drains regularly to avoid a puddle on the floor.

Changing oil is a long term thing (about 1500 to 2000 hours) but requires moving out the machine to access the back panel. It isn't a hard job removing the back panel, but you have to remember to install it somewhere that gives you plenty of room to get behind it when the time comes.

Have you ordered your machine yet? If you haven't, drop me a line and I will see what I can do to get you the best price.

Hello Ray, nice to see you here!
I thought I would start my own thread, but this one seems to be appropriate for my questions. I have just set up an LP280 together with a brand new MCH16ETS/ Super Silent for a client. TODAY; ACTUALLY!!! This is the first LP nitrox membrane I have installed, but it will probably not be the last!

Anyways, I'm looking for a solution for auto-stop on the LP, since it will of course keep running even after tanks/storage are full and the HP has switched off. Since I didn't ask for this when I made my orders with Coltri I have to figure it out myself here. My client has a 5x50L 200 bar storage, which he needs to fill up at night.

Would you have any suggestions on how to go about this, please?

Also, I cannot yet get the machines to make HP 40%. Where as the LP clearly produces up to 40%, the best results so far is about 35% HP nitrox. I suppose we need to get through the brake in period to get everything smooth, and so far it looks and sounds great. Hopefully no reasons to worry.

 

[rcontrera]

Couldn't ask for an easier installation, could you!!

I don't like the idea of an auto shutdown for the LP280. Making Nitrox and operating high pressure equipment should be something that the operator pays attention to.

Balancing out the final O2 percentage is a perfect example of why. Air compressors will automatically blow down periodically to get rid of excess moisture. When it does, it screws up the flow characteristics through the generator and the Nitrox that is made before the compressor comes back up to pressure will be just slightly enriched at best. That's why the O2 meter reading on the generator is usually different from the reading at the fill panel.

I have a fellow in Florida that dumps his filling air to training tanks during a compressor blowdown and then lines it back to the bank once the pressure is back and the Nitrox levels out. That's a lot of work, but he doesn't waster any air and he doesn't screw up his mix in the storage tanks.

Once your customer gets used to the system, he will be able to just dial in whatever pressure he needs to get whatever mix he is after. It may take a few months to become an expert, but it will come.

 

[KOMPRESSOR]

Couldn't ask for an easier installation, could you!!

I don't like the idea of an auto shutdown for the LP280. Making Nitrox and operating high pressure equipment should be something that the operator pays attention to.

Balancing out the final O2 percentage is a perfect example of why. Air compressors will automatically blow down periodically to get rid of excess moisture. When it does, it screws up the flow characteristics through the generator and the Nitrox that is made before the compressor comes back up to pressure will be just slightly enriched at best. That's why the O2 meter reading on the generator is usually different from the reading at the fill panel.

I have a fellow in Florida that dumps his filling air to training tanks during a compressor blowdown and then lines it back to the bank once the pressure is back and the Nitrox levels out. That's a lot of work, but he doesn't waster any air and he doesn't screw up his mix in the storage tanks.

Once your customer gets used to the system, he will be able to just dial in whatever pressure he needs to get whatever mix he is after. It may take a few months to become an expert, but it will come.

Thanks for answering Ray. I do agree with you, personally. However, my client has standardized his gas to 32% nitrox. Nothing else, ever. They are clam divers. And they fill up a bank of 5x50L tanks ++ once a day. Lots of gas!

I am gaining experience with nitrox membranes, rapidly, since I started from zero just days a go... I have noticed the LP280 will give a steady mix at a given pressure to the membrane, so when the mix is consistant, no turning the knob, I still feel the system can be left unattended for a while. The mix is of course checked by each diver before diving, and with a definitive limit at 30 metres (by law), the margin on the mix is fairly good as for safey, even if it should vary a little. And since the storage tanks are so large, any variations due to compressor blow downs is easily adjusted for on an average level.

So I'm just hoping there's some kind of standard components to switch down the LP280 when the HP compressor is done with it's job. Have you seen anything like this?



Hey, when I lived in WASHINGTON they used to call me RAY, since my real name is impossible to pronounce for Americans... And now I make a living on COLTRI COMPRESSORS... Are you me???!

 

[rcontrera]

Yes, you can wire in a relay into the LP280 and tie it to the main compressor. However, it is a job for an industrial electrician. Quite simple and not requiring a lot of money, but you need someone that understands motors and motor starters.