Question 1

What parameters matter when choosing a pressure transducer?

Accepted Answer

The measuring range should be chosen so that the process pressure works at 50-80% of the scale, for optimum accuracy and durability - an oversized transducer loses useful resolution. The output type also matters (4-20mA, 0-10V or HART digital signal), as do the diaphragm material in contact with the fluid (316L stainless steel for most applications, special materials for corrosive media), the process connection (G1/2 thread, flange) and the accuracy class required. For media with a risk of explosion, also add the ATEX classification of the installation zone.

Question 2

Electromagnetic or ultrasonic flowmeter - what is the difference?

Accepted Answer

An electromagnetic flowmeter measures directly the velocity of an electrically conductive fluid (water, most industrial liquids) and has very good accuracy, but does not work with non-conductive fluids such as oils. An ultrasonic flowmeter (clamp-on or in-line) works with almost any liquid, including non-conductive ones, and the clamp-on version is fitted onto the existing pipe without cutting it - useful for retrofit or temporary measurements. For utility billing or precision dosing on conductive fluids, electromagnetic remains the standard; for non-conductive fluids or quick installations, the ultrasonic is the suitable solution.

Question 3

PT100 or thermocouple - how do I choose the temperature sensor?

Accepted Answer

A PT100 (platinum resistance) offers better accuracy and greater long-term stability, and is the standard choice for temperature ranges up to about 600°C in usual industrial processes. A thermocouple (type K, J or others) withstands much higher temperatures - over 1000°C for type K - and tolerates mechanical shock better, but has lower accuracy and requires cold junction compensation. For standard processes below 500°C we almost always choose PT100; for furnaces or combustion processes, the thermocouple is the only practical option.

Question 4

Radar, ultrasonic or hydrostatic level sensor - which do I choose?

Accepted Answer

A radar sensor measures without contact with the fluid and is not affected by vapours, foam or changes in density, making it a robust choice for tanks with aggressive contents or variable conditions. An ultrasonic sensor is cheaper and works well in simple applications, but loses accuracy in the presence of dense vapours or foam. A hydrostatic (pressure-based) sensor is suited to open tanks with constant liquid density, and is an economical solution where there are no large variations in temperature or composition.

Question 5

What does ATEX certification mean for measuring instrumentation?

Accepted Answer

Instruments installed in areas with an explosive atmosphere (refineries, gas stations, silos with combustible dust) must be certified for the specific zone - 1 or 2 for gases, 21 or 22 for dust - with a suitable type of protection (intrinsic safety Ex ia, flameproof Ex d, etc.). Not every rugged sensor is automatically ATEX compatible; the certification must correspond exactly to the zone, gas group and temperature class in the installation project. Send us the zone classification and we will choose the appropriately certified instrument.

Question 6

How long does delivery and calibration of measuring instrumentation take?

Accepted Answer

For pressure and temperature sensors in the usual ranges, the lead time is 24–72 h when the item is available locally or at the supplier. Flowmeters configured for the specific diameter and fluid, or ATEX-certified instrumentation, are made to order, usually 1–4 weeks; it can take longer depending on the brand and the specifications.

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