Oil condition sensors 1

[WGJ]

Has anyone out there had practical experience of electronic oil condition monitoring in road vehicles, especially diesel?

By this I mean the use of sensors like the TEMIC sensor:

http://www.conti-online.com/generator/

http://www/com/en/contit...

Which uses the dielectric properties of the lubricant, plus algorithms in the engine control unit, to flag oil changes.

 

[Comcokid]

Sensors to measure the dielectric properties of a lubricant have been around for some time as a external device, and for a few years as a engine-mount sensor. Basically, they are capacitive in nature, and indirectly indicate the dielectric constant of the lubricant . If checked against a clean lubricant , you can measure a change in the dielectric constant. This slight change in dielectric constant results from dirt, absorbed contaminates, and water reacting with the oil. Most frequently, these sensors are used in larger diesel engines to sense presence of water in the oil - usually from coolant.

Another method used to check for 'oil quality' is through viscosity. Usually incorporating a vibrating probe or travel of a solenoid driven piston. Oil viscosity changes as the oil absorbs contaminates and the additives break down Ten years ago, I was involved in a project developing a solid-state viscosity sensor which worked very well but never reached the market.

I was unable to follow your link to see exactly the specs of the device you're looking at.

 

[WGJ]

Many thanks. I understand the theory behind the capacitive sensor, the problem is, how does it actually fare in real-world applications?
The object with these sensors usually falls into one of a few categories, depending upon the users objectives. For example:
- To string out service intervals to keep a vehicle on the road and earning money as long as possible
- To ensure that 'fatigued' oil is detected before it can do real damage to an engine
- To balance both of the above to keep costs under control

However, even with modern engines and modern oils, I assume there are still residues and deposit that build up in the engine and sensors like the capacitive oil quality devices and its this sort of experience I was fishing for.

The potential application, by the way, is in small high speed diesel engines.
I copied the link in again, see if it works this time.

http://www.conti-online.com/generator/

http://www/com/en/contitemic/contitemic/themes/press_services/archive_01/archiv_05_06_01_en.html

 

[bouncy35]

I am interested in Oil Condition Monitoring for possible use on Military vehicles. Hence i need to find data on possible sensors out there.

If anyone has info/links to information regarding oil condition sensing could they post it here.

Thanks

WGJ: i cannot follow your link so could you point me in the correct direction. I have info on the Impact Tech sensor but any other info you have that could help me would be very helpful indeed.

 

[WGJ]

Yes - looks like Continental have revamped their web site.
If you go to

http://www.conti-nline.com/generator/

http://www/start/index_uv.html

and then select 'Continental Temic' in 'Global' under 'Brake Systems and Chassis Components' then 'Relaunch of temic.com' on the page that you're taken to you'll find another link/heading called 'Portfolio Powertrain and Chassis' and this takes you to a page that mentions their oil condition sensor. Hope all that makes sense.

Since asking the first question about oil condition sensing, I've found that Bosch and Hella will be offering sensors which are claimed to sense oil temperature, level, permetivity and viscosity. The Temic did not cover viscosity.
This increases the value of the data significantly, as far as I can make out.
Like this:
Temperature - this can be used as a general guide to the reduction of a lubricant's mechanical qualities over time. Data can be used by powertrain control module software/algorithms to modify service time. 'Cold' oil may develop emulsions due to water associating with oil at low operating temperatures, necessitating early service. 'Over heated' oil may need early service owing to a reduction in it's lubricating qualities - I dare say the chemists will chastise me for attempting to describe things in this way but my job is/was to find a sensor that contributed to engine longevity, value and control.

Level - self explanatory, I think. Good for car systems where the owner doesn't know how to open the hood and couldn't find a dipstick if it was neon lit.

Permetivity - using a capacitive sensor to measure permetivity allows assumptions to be made on the acidity, soot loading and water/contaminant content of the oil. Again input to the powertrain control module and used by software/algoritms to modify the service time.

Viscosity - Using either micro-machined silicon sensors or surface-acoustic wave devices the viscosity of the oil may be assessed using the Bosch and Hella parts.

Of course these sensors are aimed at automotive mass production use rather than lab or analytical use and need a whole lot of software support for individual applications.

For development or analytical work the Lubrigard system seemed good to me and D. Peverell (Lubrigard Director) was good enough to respond to my initial enquiries.

 

[sean01]

Hi all,

I designed a portable electronic sensor a while ago for use in Military aircraft. The unit was battery powered and was about 6 x 4 inches in size and used a small photodiode laser that was commercially available at the time. The instrument operated to the requirements of ISO 4402 in that it made an assessment of the amount of contamination in the oil based on size. The instrument is patent protected by British Aerospace - but I believe that a company called UCC in cambridge england had a similar idea a few years later and found a way of getting round the patent.......... might be worth a look ?


best wishes


sean

 

[jmw]

http://www.macomtech.net/oil_analysis.htm

has a range of sensors. Not sure if any will be suitable for small engines.

JMW

http://www.viscoanalyser.com

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[piezoman]

Hello all,

See website

http://www.biode.com

with acosutic wave sensor for oil viscosity monitoring. This is new technology and we are looking to partner with OEM's

piezoman