Ex PC-Workstations, Ex-PCs

Ex Automation technology

Ex-p Pressurized enclosures

D122.A D122.PA D122.Z DM110 TA125

Digital Indicator: D122.A - Options

the D122 indicator series contain the following function and performance enhancements as option:
  1. Integrierted Ex i- barrier module (D122.A.x.x.BM)
  2. Integrierted 2- wire transmitter (D122.A.x.x.MU)
  3. Special software enhancement - curve- and square root fitting (D122.AS.x.x.x)

1. Integrierted Ex i- barrier module

To operate the indicator (D122.A) resp. totalizer (D122.Z) in non intrinsically safe 4 .. 20 mA current circuits in hazardous area.

The standard digital indicator D122 works exclusively in intrinsically safe 4..20 mA current circuits (Ex i). If the concerned measure current circuit is not intrinsically safe, the indicator needs an extra zener barrier or an isolated interface as well as a long additional cable to the interface in save area and the same way back.


In those cases, the option integrated zener barrier is very practical.

A further advantage of an indicator with this option is that the intrinsical safety proof is not required.

The ignition protection is Ex [ib Gb] ib q IIC T4 Gb.

The terminal voltage in the measure circuit with internal zener barrier option is about 2 V.

This option is available for all housings, excluding the small control panel housing (48 x 96 mm). The field housing depth expands from 64 to 82 mm.

A combination with the option integrated transmitter is not viable.

To order the integrated zener barrier option use the following type code: D122.x.x.x.BM.

2. Integrated 2-wire transmitter option

Using the integrated 2-wire transmitter for head mounting option, a sensor e.g. a PT 100 can be connected directly.


The digital indicator series with field housing can be equipped with a customised intrinsically safe 2-wire transmitter for head mounting, according to DIN 43729 type B (max. height = 30 mm).

With this option, it is possible to connect a sensor, e.g., a PT 100 directly to the digital indicator D122.

Terms of use

By ordering, specify the desired transmitter so GÖNNHEIMER will include it. GÖNNHEIMER can also try to insert your provided transmitter.

This option is only available for indicators with field housing. The field housing depth expands from 64 to 82 mm.

A combination with the internal zener barrier option is not possible.

To order the integrated transmitter option (MU) use the following type code: D122.x.x.x.MU

3. Special software enhancement - curve- and square root fitting (D122.AS.x.x.x)

The standard digital indicator D122 has a linear relation between measured and displayed current value - the option special software offers the possibility to program any monotone function between measured current and displayed value!

Non linear curve fitting:

The curve fitting software indicates the measure current in a nonlinear way. Consider an application of a filling-level meter for a spherical tank. The measure current is linear to the filling height of the liquid, but the function between the filling height and the volume is non linear. To get the correct quantity indication you require a list of points, which shows the connection between measure current and as-sociated quantity inside the tank.

The curve fitting software of the D122.XS interpolates the curve between these points with a first (linear) or a second (square) order polynomial. The linear interpolation requires a list of 17 points - the square interpolation needs 33 points.


Square root fitting:

To program a square root function, e.g., to display the flow through an aperture, a special square root fitting feature is available. For this option, it is not necessary to enter a long list of points, but just a start and an end value (associated flow by 4 and by 20mA measure current). The indicator calculates automatically the selected points for interpolation. The measure error is less than 0,1 % full scale, if measure current is more than 5 mA.

To order the special software option use the following type code: D122.AS.x.x.x

  last modified: 07.01.2016