To calibrate a pressure gauge, first ensure it is clean and free from any damage. Connect the gauge to a calibrated pressure source, such as a pressure calibrator or a known reference gauge. Gradually increase the pressure and compare the readings on the gauge to the reference value at multiple points across its range. Adjust the gauge as necessary, following the manufacturer's instructions, to ensure accurate readings.
Adjust by link, sector & pinion
To calibrate compound gauges, you will need a calibration pump and a pressure calibrator. Connect the compound gauge to the calibration pump and apply pressure using the pressure calibrator. Compare the readings on the compound gauge with the readings on the pressure calibrator and make necessary adjustments to bring them into alignment.
The difference between Absolute Presure and Gauge Pressure is 14.7psi. So zero gauge pressure (0psig) = 14.7 psia. 600 psig = 614.7 psia. Calibrate the tranmitter so 4mA is obtained at 14.7 psig and 20mA is obtained at 614.7psig. The span will be 600 psi in both cases.
you need to check it against another gauge that is accurate which should be calibrated by a pressure calibration lab. So at least you know that the gauge you use to test your oil gauge is right. Then just "tee" in the "master" gauge into your oil line and check the two gauges against each other when the engine is running.
I use a fuel pressure gauge.
A compound gauge is a pressure gauge that displays both negative and positive gauge pressure measurements. Gauge pressure is a measurement of pressure relative to ambient pressure. For example, if ambient pressure was 14.7 PSI and you were to measure absolute vaccum using a compound gauge, the gauge would indicate -14.7 PSI.
Gauge block.
step-1:remove the pressure gauge from the equipment when machine is in off condition. step-2:remove the cap and glass of the gauge. step-3: remove the needle of the gauge with a needle puller( a special tool ) step-4: place the same needle indicating zero. step-5: fix the glass and cap as usual. step-5: check(calibrate) the gauge on a dead weight tester with a master degital pressure gauge.
Place the gauge inside a sealed piston. Place the weight on top of the piston and read the pressure from the gauge. The force exerted by the weight multiplied by the area of the piston will give you the actual pressure exerted on the gauge. Using SI units. A 5 kg weight placed on a 0.25 meter diameter piston will create a pressure of around 1 pascal (Nm^2). 5N*Pi*0.25m^2.
Assuming we are using a pressure transducer to measure barometric pressure, I understand that a gauge type transducer would be used. The internal diaphragm would have a fixed pressure behind it (at a guess would be at standard temp/pressure, STP, ie 20 deg C @ 1013mb), so the transducer has a reference to work against. The front of the diaphragm would be exposed to atmosphere. I would assume the reference (gauge) pressure would vary as the barometric pressure varies, as the diaphragm would move towards the side with least pressure, or at 1013mb the diapragm would be in the centre (which could be used as the null output voltage), higher than 1013mb could produce a positive voltage swing, less than 1013mb could go negative. This is all I can think of, please let me know if on the right track.
The gauge pressure is the absolute pressure minus atmospheric pressure. If atmospheric pressure is considered to be 101 kPa, then the gauge pressure would be 219 kPa.
Gauge pressure usually refers to the pressure difference between ambient, atmospheric pressure and the pressure in a vessel or line. A gauge pressure of zero would mean that the vessel or line was at atmospheric pressure. Normally the pressures of interest are ABOVE atmospheric so the gauge pressure is positive. Vacuum gauge pressure measures how far BELOW atmospheric pressure a vessel or line is. As such vacuum gauge pressure may be measured as a negative number - or for convenience it may be reported as a positive number with the caveat that it is "vacuum gauge pressure", meaning that the reported pressure is how far atmospheric pressure is above the pressure in the vessel or line.