Mechanical vs digital or wireless pressure gauge
Mechanical pressure gauges are simple, cheap devices with local displays that show the pressure at a certain point in your process. This is one of the oldest forms of pressure measurement and it is still very common. Digital pressure gauges seek to bring this important measurement into the 21st century by adding analytics and wireless communication features.
While classic mechanical pressure gauges are very reliable, digital pressure gauges are becoming more and more common and will likely become even more popular with the advent of the Industrial Internet of Things (IIoT) due to their wireless capabilities. The article here talks about the difference between mechanical and digital pressure gauges.
Pressure gauge types
Mechanical pressure gauge
Most mechanical pressure gauges don’t communicate with the process controller. A mechanical pressure gauge uses a mechanical system to measure pressure, with a Bourdon tube expanding and contracting based on the pressure applied. The entire system – rack, pivot, spring, pinion, and pointer – moves to show the pressure on the dial. It’s simple, yet effective.
We might have already encountered dials like this on a tire pressure gauge, fuel pressure gauge, oil pressure gauge, or in any other everyday situation where pressure should be measured in a cheap and reliable way.
Mechanical pressure gauges are very common and easy to read, but this is also their greatest limitation: we have to put our face next to it to read the pressure, which might be the simplest solution for your garden sprinkler’s water pressure gauge but can result in a lot of walking around, putting our face in dangerous places and recording numbers if we are working in a factory.
Wireless or digital pressure gauge
Pressure Gauge has the same design as a mechanical gauge, but it offers the option of communicating through wirelessHART. With the HART communication protocol, we can monitor process value and diagnose problems in the device or process.
The wireless pressure gauge uses a strain-relief sensor that processes the signal digitally. Then it imitates the old interface with a tiny motor driving the pointer on the dial.
A wireless or digital pressure gauge gives more stable and accurate pressure measurements, already converted to digital. And most importantly, the data can be collected remotely, without someone walking to every pressure gauge in a facility and noting down the numbers.