FAQ

Process transmitters

Can a 3-wire transmitter also work in a 2-wire configuration?

No.

Can each pressure transmitter measure any medium?

No, the materials stated in the data sheet are to be checked by the customer for resistance.

Can the connector be altered?

The electrical connection cannot be altered.

Can you switch between 4 ... 20 mA and 0 ... 10 V?

No, the output signal is defined in the order and cannot be changed.

What causes zero point drift?

Through the ageing of the electrical components, through temperature and load cycling.

What solutions are there against pressure spikes?

For this, we recommend a process connection with a reduced pressure port of 0.6 mm or 0.3 mm.

Will a pressure transmitter also work without a power supply?

No.

What does NAMUR stand for?

NAMUR is the abbreviation for "Normenausschuss Mess- und Regeltechnik" (Standards committee for measurement and control).

What is ATEX?

ATEX is a widespread synonym for the explosion protection directives of the European Union and is derived from the French abbreviation of “Atmosphere Explosible”. There are currently two directives in the field of explosion protection, namely the ATEX product directive, 2014/34/EU, and the ATEX workplace directive, 1999/92/EC.

What are the signalling values in accordance with NAMUR?

NAMUR Downscale: 3.5 mA
NAMUR Upscale: 21.5 mA

What do the designations of Temperature Class mean?

The ignition temperature is the lowest temperature at which an inflammable mixture of gases can ignite at a flame, a hot surface or otherwise generated spark. Gases and vapours are divided into Classes in which the temperature of the surface must always be lower than that of the mixture. (T1 > 450 °C, T2 > 300 °C, T3 > 200 °C, T4 > 135 °C, T5 > 100 °C, T6 > 85 °C).

What do the Zones in explosion protection mean?

Gases:
Zone 0 (Category 1): permanent or long-term danger of explosions
Zone 1 (Category 2): hazardous atmosphere occasionally exists
Zone 2 (Category 3): explosive atmosphere exists only rarely, and then only for a short time

Dusts:
Zones 20, 21, 22 with the same meanings

What is the value of the current at the output limits in accordance with NAMUR?

Lower output limit in accordance with NAMUR is 3.8 mA (other value possible)
Upper output limit in accordance with NAMUR is 20.5 mA  (other value possible)

What is the overpressure limit?

Pressures up to the overpressure limit will not cause any permanent damage to the measuring instrument, however, the error limits specified in the data sheet could be exceeded.

At what pressure could the pressure measuring instrument be destroyed?

Pressure values above the overpressure limit can lead to irreversible damage of the measuring instrument. It does not matter whether this pressure is present constantly or only for a short period of time. In either case, the complete destruction of the parts exposed to the pressure and the sudden escape of the pressure medium can be expected.