Analytical Instrumentation

What is Zero suppression & Zero Elevation?

Zero suppression & Zero elevation are values that correspond to the 4-20mA transmitter range for level measurement using Differential pressure transmitter (DPT).

In signal conditioners, in particular, zero suppression and zero altitudes relate to a reduction (deletion) or angle (altitude) of the nominal “zero” yield so that it is not at zero volts (or milliamps).

Where Zero elevation & Zero suppression?

The aim of calibration elevation & suppression is to add differential pressure to circumstances where a 4 mA output is required at a point other than 0 differential pressure.

A typical implementation for this is where a device producing a +/- 10-volt signal is to be used and this signal is to be taken into an input of 0-10 volts. You would need to “elevate” the zero point to + 5 volts and rescale the variety to fit within 0 to 10 in order to use the complete assessment variety.

Zero suppression:

Consider a closed tank, level of liquid in it will be measured using Differential pressure transmitter.

If you mount the transmitter below the tank’s datum line, when the High-end impulse line fills up, the transmitter signal will exceed 4 mA and this will result in a zero error relative to the real zero level of the tank. So that head pressure must be suppressed. By changing the signal to 4 ma. This is the suppression of zero.

Zero Elevation:

If the transmitter is mounted above the datum line, the signal must be raised from 4 ma to prevent a mistake when the hi-side impulse range is filled. This is a zero elevation.

if you are using a transmitter with HART protocol you can do this just by changing the cal range using the HART communicator

Related posts

Photovoltaic Detectors

Sivaranjith

What is proactive maintenance?

Sivaranjith

What is the Difference Between AC and DC Capacitor?

Rabert T
Follow Us on LinkdIn