Need an Oxygen Sensor. Sensor experts please help.

[savingraysprivates]

Hi Guys,

Anyone know who I can contact in order to find a cost effective oxygen concentrator for my needs? I have attached a PDF of the requirements.

I have search high and low, and most places either offer a full instrumentation suite costing over $1000, or sensors made only for small appliance and ambient sensing. I was only able to find one supplier so far that would have been feasible, but they want to charge $600 for a 1" x 3" sensor.

I already sourced through globalspec and thomasnet.

Let me know where I should check, any help would be apprciated.

Thanks!
Ray.

 

[elevmike]

$50.00-$250.00??? I think your specifier should stick to fixing his Chevy rather then writing specs for water treatment facilities. This is the problem, he walked out of Pep-Boys thinking at an industrial O2 souldnt cost any more then that little plug thing in his exhaust manafold.

 

[savingraysprivates]

Can we please stick to posts that are actually helpful?

If you could recommend something that may be within $300 to $450 would also be helpful.

 

[Ken Moore]

Any industrial grade instrument for less than $1000.00 is a deal, I would go for the 600.00 model and consider myself lucky. The only way you will get the pricing you want is if you are going to need thousands of these things, and work out sometype of bulk pricing with an OEM sensor company.

Whoever wrote that spec, with that low of price expectations never worked with industrial applications. In my field, price is never part of the spec anyway, you write all the performance data, service requirments, material of construction etc... then send the spec sheet to various vendors for quotes. That's when you get the pricing. Then with REAL WORLD pricing in hand, you submit your request for funding.

 

[elevmike]

Ok so I appologize for being a smart a$$, but the cost figure in the spec is unreasonable. Omega has a sensor for about $700.00. As Ken said, you've found the best deal your going to get.

 

[rdrast]

The responses aren't out of line, your expectations are. $250 for an oxygen sensor? $250 will probably get you an automotive sensor as stated above, but they do not meet the specs at all.

Most combustion-control O2 sensors (the cheap ones) used in automotive and burner applications can only read a concentration from 0 to 25% free O2. Something that can read 0 to 100% O2 is going to be fairly pricey. Good luck though.

 

[Tom Jenkins]

For process control you want to get a good sensor. There are a number out there - BWT, Endress Hauser, Analytical technologies are some we looked at.

Buying a cheap transmitter to control a sophisticated process is the most foolish type of false economy. You want the lowest cost sensor THAT WILL ALWYS PERFORM ADEQUATELY. You are unlikely to get that from a $50.00 sensor.

There are some monitoring devices out there, such as MSA and others, that are used for personell hazards and to control ventilation fans in parking structures that may be in the price range you want. I doubt that they are going to get you the accuracy your application seems to need.

 

[savingraysprivates]

Hey Guys,

Found something. Please see attachment. $136.50.

Can come with it's own enclosure, but I will probabbly mount it in my own.

What do you think?

Thanks!
Ray.

P.S. How do you like my new avatar?

 

[Tom Jenkins]

It meets your price requirements. It appears to be designed for your application.

Are you sure it meets your specs?

Output 0-0.95 VDC (is this enough resolution with the PLC card?)
Accuracy ±2% (is this good enough?)
Power 18 VDC (does this match your other power suppies?)
15 lpm flow (do you already have a sample pump?)

 

[savingraysprivates]

1 - I can order it with 4-20ma
2 - +- 2% is good enough
3 - Not sure, but it's already been discussed around here to include a 12V transformer for our smaller instruments
4 - I will be taking a sample from the main line by the way of a needle valve.