Guide to buying pressure gauges
The pressure gauge is the key device for traveling with peace of mind on the road and keeping our tire pressure at bay. A product that we can find in many gas stations, but with the disadvantage that, many times, it is deteriorated, not reliable or, even worse, they even force us to pay to use it. That is why you may be interested in getting a personal pressure gauge, even more so seeing how much it costs. A search that we make easier with our guide to buying the best pressure gauge and the advice that we offer you below.
Pressure gauge type per connection
If we look at a comparison of pressure gauges we will see how many existing options are. In order to segment this entire range, we are going to look at various aspects, which will guide you when it comes to finding an inexpensive and quality pressure gauge. And to begin with, we will talk about the type of pressure gauge according to its connection.
In the market we can find independent pressure gauges and others connected. The independent ones are those that serve to measure the pressure anywhere, without the need for a compressor or similar. Obviously, they are models that do not serve to inflate wheels but only to measure their pressure.
If what we want is to measure the pressure of the tires and be able to inflate them, then it is necessary to have a pressure gauge connected. These are the pressure gauges that we see in workshops and gas stations, which are connected to an air compressor with which to offer that possibility of inflation that we need. So, depending on what you want to do, you should choose one model or another.
Analog or digital
Traditionally, pressure gauges have always been analog, with an oscillating needle depending on the measured pressure, which moves on a dial set and regulated with the different pressure levels that the device can measure. A simple solution that, today, offers a high capacity of visibility, although you always have to fix your eyes to find the exact measurement.
To solve this small annoyance today we have digital pressure gauges. These devices do away with the stylus and dial and replace it with a good-sized, usually backlit LCD screen. Once the pressure gauge valve is placed and the activation button is pressed, we will see the corresponding measurement on the screen and in the measurement unit that we have chosen. A simplified method that makes it easier and clearer to see the pressure of our wheels.
With these two parameters we already have elements to discard nanometers that do not interest us from our selection. But there is one that is key to our choice: the working range of the device.
As with air compressors, pressure gauges also work with different pressure ranges or capacities. So, depending on the pressure that the vehicle with which we are going to work needs, this should be the acceptable pressure range or measurable by the pressure gauge.
For reference, a pressure gauge of 0 to 4 bar is more than enough to monitor the pressure of cars, motorcycles, bicycles and even light vans. However, in the event that we increase the size of the vehicle, as happens with large vans, trucks or buses, it is necessary to expand the measurement range. The most common for these uses is the one that ranges from 0 to 11 bars, although for extreme cases we can even have manometers capable of measuring up to 18 bars of pressure.
At this point, we already have all the necessary elements to choose a safe and suitable pressure gauge for our needs and preferences. But there are still a couple of things that can be useful to you in making your final decision.
One of them is the construction of the pressure gauge. On the market we find from inexpensive gauges with an upgradeable construction to professional models, designed for intensive workshop use and capable of withstanding the harshest conditions. There are tastes and prices, so depending on what you need and prefer you can choose one option or another.
The other issue to assess is size, in the case of independent gauges. If you plan to use it on the road, take it in the car or on your motorcycle, you probably want the product to be small in size and light in weight. Luckily, it is something that manufacturers have taken into account and that we can also easily find among the wide range of nanometers currently available.
Frequently asked questions
Q1: How does a Bourdon gauge work?
The Bourdon manometer was an invention of the French engineer Eugene Bourdon and dates back to 1849. A device that has certain similarities with current manometers, since at that time it used a similar system to measure pressure. Specifically, this manometer consists of a tube curved about 270 degrees with one end closed and the other open. Depending on how much or how little the internal pressure varied, this tube moved a needle, located on the other side, to indicate to the user which was the corresponding pressure of what it was measuring.
Q2: What are the advantages of an approved pressure gauge?
An approved pressure gauge is one that has undergone a certification process in which it has been subjected to a series of tests, in accordance with what is established by the corresponding approval standard. Therefore, an approved pressure gauge offers us the additional guarantee that the product has been tested and verified, offering readings of higher quality and precision than one that has not gone through this process.
Q3: How do you read a pressure gauge?
In the case of an analog manometer, the reading is made on the indicated scale, seeing where the needle points once the measurement is made. It is very important to be clear about the measure on which we are measuring (PSI, bars, etc.) to know if the pressure is adequate or not. If you have a digital pressure gauge in your hands, the process is simpler, since after the device is turned on, the measured pressure will appear on the screen together with the corresponding unit.
Q4: What is a maximum needle gauge for?
The maximum needle is an element that tells us what is the maximum value that the pressure on a digital manometer has touched. This needle stays at this maximum until it is reset and only moves if a new maximum in pressure is reached. This type of pressure gauge is not usually used for tire pressure measurements but for other types of uses, mainly industrial ones, in which excess pressure in a closed circuit can have serious consequences.
Q5: How is a pressure gauge calibrated?
To calibrate a manometer, it is connected to a controlled circuit, which has an air pressure generator and a control system that allows creating exact pressures. During the process, different pressures are generated, within the working range of the manometer, verifying if the readings correspond to the pressures that have previously been generated. If these pressures are correct then the pressure gauge would have passed the calibration, while if they differ from these beyond what is established by the standard or precision of the device, the calibration would be negative.
Q6: Which is better, digital or analog pressure gauge?
It all depends on our preferences, the truth. If it is true that it is much easier to see the exact pressure readings in a digital model, since they are reflected numerically, without having to see and count lines. But it is also true that in analogue pressure gauges we see the variation in pressure at the moment, both when inflating and deflating the tire. So, as we say, everything is a matter of preferences and the use that we are going to give the product.
Q7: How to know when a pressure gauge is unreliable?
The best way to verify that a pressure gauge is performing as it should is to compare your measurements with those of an approved or quality verified gauge . If they are very different, it is possible that the pressure gauge that we are evaluating is faulty. Something similar happens if, after taking some measurements in a row on the same tire, their results are very different. Ultimately, we can always calibrate said pressure gauge, to verify if it is in condition or not.
Q8: Is pressure gauge and barometer the same?
Although both devices are used for pressure measurement, the truth is that they are two different elements. In the case of the manometer, this is used to measure pressures in closed circuits such as tires, compressors or machinery. In the case of the barometer, this is used to measure ambient pressure, using an open system. That is, a barometer does not need hoses or other elements to proceed with the pressure measurement.
How to use a pressure gauge
The process of using a pressure gauge is almost as important as the quality and precision of the device itself, since if we use it incorrectly, it is highly likely that it will be useless. Therefore, we are going to give you below some guidelines on how to obtain precise measurements in a simple way.
Always cold tires
As a preliminary step, it is important to remember that the tires always have to be cold when taking a measurement. This means that the vehicle should not have rolled in the minutes prior to the measurement, or at least no more than five kilometers and not very high speeds. Remember that tires get hot from friction and this increases the volume of interior air.
Placing the vehicle
In addition to having cold tires, the vehicle also needs to be on a flat surface. This ensures that the weight of the vehicle is distributed evenly between these tires and does not fall more on one than on others, as would happen if we park on a hill, for example.
Removing the plug
As the last previous step, we will remove the valve cap and blow inside it to remove the remains of dust and dirt that may be inside. Do not forget to store the caps well, to place them again once we finish the pressure review process .
Placing the valve
To measure the pressure, it is necessary to place the pressure gauge valve on the tire valve, making sure that it fits perfectly and there is no air leakage. In some manometers we have a kind of trigger on the valve, which does not activate the measurement until it is released, thus helping us to place said valve without losing air. If necessary, keep the valve tight during the measurement process.
Once we have released the trigger and placed the valve we will have the measurement at the moment on the screen, in the analog models. In the case of digital ones, it is likely that we will have to press the power button or measure to obtain the reading. In any case, be clear about what you are measuring (bars or PSI) since a confusion in the measurements can have catastrophic consequences.
Adjusting the pressure
Virtually all gauges have a spigot to release air from inside if necessary. However, if your tires are hot you should not release pressure, in order to avoid leaving the tire with less air than it should. In case you have a pressure gauge connected to a compressor or air pump, you will also have a lever to inflate them to the correct pressure.
Finishing the process
To finish the process, we only have to remove the valve from the tire pressure gauge and put the cap back in its place, making sure that it is well placed and closed. A misplaced plug can be a cause of air leakage or premature deterioration of the valve and its interior.