Undepletable oxy sensor?

[HeXx]

Any opinion on this kind of sensor?

Was looking for one for my diy nitrox analyser and stumbled upon this sensor.
Could it be a candidate to replace the commonly galvanic used ones?

Cheers

 

[GF99/99]

Solid state sensors have been around for a while now great technology and if you can afford yes this is the future of O2 sensors. I would love for these to become mainstream available for rebreathers but were just not there yet.

I think Poseidon is the only company I know of that markets these for there rebreather mainly for military use but it is available to the public. I think there about $1,000 per sensor last time I checked.

 

[OTF]

Rebreathers will make a big jump forward in safety, reliability, and probably popularity as soon as these can interface easily with Shearwater electronics.

F*** galvanic sensors.

I don't even care how much the new optical sensors cost. Dying less is worth a great deal of money.

 

[kelemvor]

The SST luminox optical sensors are no good for our purposes. They only range from 0%-25% O2. Someone makes optical sensors that measure higher concentrations but it doesn't appear to be SST. Datasheet1 Datasheet2

SST does make a zirconium sensor that ranges up to 100% and is supposed to have a 10 year lifespan. I couldn't find a price on those.

 

[nadwidny]

The SST luminox optical sensors are no good for our purposes. They only range from 0%-25% O2. Someone makes optical sensors that measure higher concentrations but it doesn't appear to be SST. Datasheet1 Datasheet2

SST does make a zirconium sensor that ranges up to 100% and is supposed to have a 10 year lifespan. I couldn't find a price on those.

We had zirconia sensors in our O2 analyzers at a lab I worked at. Super fast response. Good to .1ppm accuracy. However if I recall they had to be heated to 700C to work.

Womp Womp. So much for scuba applications.

 

[HeXx]

The SST luminox optical sensors are no good for our purposes. They only range from 0%-25% O2. Someone makes optical sensors that measure higher concentrations but it doesn't appear to be SST. Datasheet1 Datasheet2

SST does make a zirconium sensor that ranges up to 100% and is supposed to have a 10 year lifespan. I couldn't find a price on those.

Yes indeed. I sent them an inquiry about the possibility to do 0-100% o2 optical sensors.

We had zirconia sensors in our O2 analyzers at a lab I worked at. Super fast response. Good to .1ppm accuracy. However if I recall they had to be heated to 700C to work.

Womp Womp. So much for scuba applications.

Always good for handheld shop analysers.

In the meantime I'm doing some research on the matter and i intend to try and develop an all in one solution, optical sensor for 0-100% o2 and thermal coefficient with differential for He% analysis.

 

[Wibble]

How well do they cope with moisture in rebreathers?

 

[kelemvor]

We had zirconia sensors in our O2 analyzers at a lab I worked at. Super fast response. Good to .1ppm accuracy. However if I recall they had to be heated to 700C to work.

Womp Womp. So much for scuba applications.

Must have been a different brand. The SST zirconia sensors are rated for -100c to +400c. The top end temp depends on sensor model. Some peak at 50c, others 400c or something in between. All of them work down to -100c. Source: Zirconia Oxygen Sensors | Sensing Technology

 

[-JD-]

I'm thinking that these Zirconia sensors might not be ideal for rebreathers, especially since they don't like high humidity or silicone off gassing and require a constant heater supply of approx 4.3V at 1.8A.

5.1.2 Operating in Aggressive Humid Environments
When operating the sensor in warm, humid environments it is important the sensor remains at a higher temperature than its surroundings, especially if there are corrosive components in the measurement gas. During operation this is less ofan issue as the heater operates at 700°C, however this means when the sensor or application is being powered down the sensor heater must be the last thing to be turned off after the temperature of the surroundings have suitably cooled.Ideally the sensor should be left powered or at a lower standby voltage (2V typically) at all times in very humid environments. Failure to adhere to these rules will result in condensation forming on the heater and sensing element. When the sensor is re-powered the condensation will evaporate, leaving behind corrosive salts which very quickly destroy the heater and sensing elementas illustrated in Figure 5-1; note how the sensor’s external metalwork looks completely normal.

https://sstsensing.com/wp-content/u...-Sensor-Operation-and-Compatibility-Guide.pdf
https://sstsensing.com/wp-content/uploads/2016/05/DS0080rev4_O2S-FR-T5Datasheet.pdf

 

[nadwidny]

Must have been a different brand. The SST zirconia sensors are rated for -100c to +400c. The top end temp depends on sensor model. Some peak at 50c, others 400c or something in between. All of them work down to -100c. Source: Zirconia Oxygen Sensors | Sensing Technology

The rating is for the temperature of the gas being measured. The sensor itself was heated to ~700C.