3 Operation and system construction
32
2.2 What is delivered?
- Field display, model to order.
- Operating manual.
- Accessories as ordered.
2.3 Certification
CE mark, conformity certification
The unit has been manufactured using state-of-the-art technology and
has left the factory in perfect working order. The unit complies with
relevant regulations as well as the IEC 61010 "Safety regulations for
measurement, control and laboratory instrumentation" directives.
This means that the unit described in this operating manual
fulfils the legal requirements laid down in the EU directives. The manuf-
acturer acknowledges successful testing of the unit by adding the CE
mark to it.
3
Operation and system construction
3.1 Measurement principle
The field mounted display is directly connected to a 4 to 20 mA current
circuit. The energy required to power the unit is derived from the cur-
rent loop. The unit monitors an analogue measured value and shows
this on an easily read LC display. Additionally, the measured value is
also shown in the form of a bargraph.
Increased readability in dark areas is achieved by the addition of a illu-
minated display.
3.2 System construction
Micro-controller controlled field mounted display with rear illuminated
numeric and analogue LC display. Display update is made every second.
The dynamic internal resistor (load) makes sure that the signal circuit
voltage drop is always < 2.5 V.
Digital field display