Igema EWLS, Инструкция по установке и эксплуатации

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H3
H6
H7
H4
H5
H2
H1
4.2 Function
The detection is done by a conductive measuring principle, which requires a minimum
conductivity of the liquid. The conductivity of the medium is measured in the unit µS/cm. The
conductive measuring method makes two statements: electrode immersed, or electrode
immersed.
The measuring unit (MU-3) can be equipped with up to 4 probes. Their spacing can be
determined by the customer.
Both the measuring unit and the control unit have 2 independent electronic circuits with their
own processors. All processors perform a regular self-check for internal errors of the electronic
circuits.
The control unit (CU-3) processes the acquired signals and controls the downstream functions.
It is installed in a steel housing (IP65/NEMA4X). In the switch housing there are two lamps per
electrode (water=green, steam=red), normal operation (green LED), water alarm (yellow) and
system error (yellow):
System Status LED on
Status of
probes
Arrangement of the lights on the switch box door
Normal
Operation H1, H5,
H7 All probes
in steam
System error /
Physical state
not possible
H1, H2,
H5, H6 Probe 1 in
Steam
Probe 2 in
Water
Water alarm
Visual Warning
H1, H4,
H7,
H3 blinkt
Probe 1 in
Water
Probe 2 in
Steam
Water Alarm H1,
H4,H6,H
3 Probe 1 in
Water
Probe 2 in
Water
One contact (SPDT) is permanently connected as a signal contact for device errors. Signalling
(e.g. for PLC) for the 4 probes is done via a separate output contact each. Each processor
controls its own relay per contact, whereby the output contacts are only switched when both
processors signal the normal operating state in unison. In addition, a 4mA - 20mA interface is
available as an output. For each immersed probe, the output is increased by the corresponding
proportion (16 mA / number of probes). In the event of an error, the output goes to 2 mA.
Programming is done via 4 buttons and a 2-row LCD display with 16 characters each. The
LCD display is also used for local error indication, such as failure of a supply, probe error,
display error (water over steam), electronic error as well as cable error (break or short
circuit). The local display, which is visible from a distance, informs the user of the system
status. If a fault occurs in the system, it is displayed immediately.