wtw TresCon UNO A111, Operating Manual

Page: 85 / 208

TresCon UNO Operation
5 - 29 ba43134e08 05/2017
5.3 Relay functions
5.3.1 General information
The analyzer has 12 relays that are independent of each other and can
be linked to the analyzer module. The following functions are possible
for a relay output:

Proportional controller (Frequency controller or Pulse-width control-
ler, see section 5.3.2)

Limit indicator (see section 5.3.3)

Indicator contact for a monitored event (see section 5.3.8)
Relay action The following actions of the relay can be laid down in the Action setting:
Note
In the case of monitoring functions, select Normally closed for the relay
action.
5.3.2 Proportional controller: Basic information
In the case of proportional control, a relay switches cyclically on and off
in a defined measured value range (proportional range). At the same
time, the relay switches with a:

duration of operation that corresponds to the measured value
(pulse-width controller, see page 5-30) or

switching frequency (frequency controller, see page 5-32).
Proportional controllers can be used in the following way:

Regulation with a single relay:
a regulating range with
Start value and End value is defined. No
regulation takes place above and below the range of regulation (see
page 5-30).

Regulation with two relays:
a regulating range with
Start value and End value is defined for each
relay. One relay regulates in the upper range of regulation and a
further relay in the lower range of regulation (see page 5-30).
Settings Explanations
Normally closed The relay should open if any event occurs.
Normally open The relay should close if any event occurs.