Flow meters help you measure gases, liquids, or steam in your piping system. However, not all meters have the same accuracy capabilities, so you need to do some research before you decide which products to buy.
Read on to learn about the three main factors you should consider before you shortlist products.
1. Margin of Error Accuracy
No flow meter is 100% accurate. Their measurements can be affected by operating conditions and other factors when you use them.
So, meters usually have a margin of error accuracy figure. This tells you the spread of results you get when you take readings. It also helps you choose which product is the best fit for your application and measurement needs.
For example, if you have regular accuracy requirements, then a meter with a +/- 10% capability might work well. However, if you need more accuracy, then you should buy meters with a lower figure. For example, a meter with a +/-5% rating will give you more exact readings.
Remember to match these ratings with the materials you will test. A flow meter can have variable margins of error figures depending on whether you use it on gases, liquids, or steam.
If you need to take multiple readings in the same conditions with unchanging variables to compare them or build a data set, then you need to source meters with high repeatability ratings. If a meter doesn't produce similar results on repeated readings in these circumstances, then it might not be accurate enough for your needs.
Repeatability is given as a percentage. So, for example, a meter with a rate of +/- 0.1% has lower repeatability accuracy than one with a rate of +/-0.05%.
Repeatability also helps you work out how accurate a flow meter will be. If a meter has high repeatability, then it is more likely to give you accurate results.
Before you choose a flow meter, you need to know your measurement scales. You should choose a device with the right incremental resolution for your needs. This resolution affects the useability and usefulness of your readings.
For example, say you need to measure pressure on a pounds per square inch (PSI) basis. If your meter has a 1 PSI capacity, then it can't give you an incremental reading. It rounds up results to the nearest whole number.
While this is good enough for some measurements, it won't work if you need to drill down more precisely. Here, you would need a meter that works in increments of a whole PSI.
To find flow meters to suit your applications, ask your supplier for advice. You'll get the best results and performance if you buy from manufacturers with a strong reputation in this sector. For example, make sure to ask your supplier about Coriolis flow meters.