Oil pressure sending units

[zahc]

I'm looking for low-pressure transducer for a beverage dispensing application.

I need to measure 0-30 or 0-60PSI. I thought an oil pressure sensor is probably a good source of cheap transducers. Proper laboratory-grade ones are hundreds of dollars.

Is there some standard for oil pressure guage (or for automotive gages in general)? Do they put out some agreed-upon full-scale voltage? Some agreed-upon resistance range? Most of them seem to have one screw terminal.

Summit has plenty of them but absolutely no info on how they work.
http://www.summitracing.com/parts/bck-201-0262/media/images
http://www.summitracing.com/parts/sum-g2985-1s/overview/
http://www.summitracing.com/parts/sun-cp7577/overview/

[Triphammer]

 Given it's electrical not mechanical. Automotive gauges are usually some resistance in the ground leg to the meter. 12 volts (pos) DC fed to the gauge. Neg leg to the sending unit. The gauge is not grounded by it's mount other than the lighting circuit.

[zahc]

So all the other gages move when the electrical charging system gage moves? Interesting.

[Triphammer]

So all the other gages move when the electrical charging system gage moves? Interesting.

A little bit. Not that you'd notice day to day. There is, at least up into the late 80s an electro-mechanical vlotage regulator for the gauges that holds the oil pressure & fuel gauge to about 11volts regardless of charging voltage.

[Hawkmoon]

The oil pressure gauge in my Jeep Cherokee is basically an ohmmeter. The sender has a range of 0 - 88 ohms, and the gauge is calibrated from 0 to 80 psi.

That's for an '88 Cherokee. I believe after Chrysler bought Jeep they changed the range to go from 8 to 104 ohms, but the gauge still reads 0 to 80 psi.

I think any basic, automotive electric oil pressure gauge kit would work for you. My recollection is that the Jeep system is 12v positive through the gauge, and the variable resistance sender is in the ground side of the circuit. (Which seems logical, since it screws into a brass fitting on the side of the block and the block is grounded.)