15
G
Mounting and Installation
Connecting scheme
Parallel operation
Connecting scheme
Individual operation
Circuitry
Circuitry
0...10V
0V/GND
0...10V
0V/GND
Power supply
AC 24V~
0V
DC 15-36V = GND
Circuitry
0...10V
0V/GND
V
Power supply
AC 24V~
0V
DC 15-36V = GND
SUPPLY VOLTAGE :
For operating voltage reverse polarity protection, a one-way rectifier or
reverse polarity protection diode is integrated in this device variant.
This internal one-way rectifier on AC supply voltage.
The output signal is to be tapped by a measuring instrument. The output
signal is measured her against zero potential (O V) of the input voltage!
When this device is operated on
DC supply voltage
, the operating voltage
input UB+ is to be used for 15...36 V DC supply and UB – or GND for
ground wire!
When several devices are supplied by one 24 V
AC voltage supply
, it is to
be ensured that all ”positive“ operating voltage input terminals (+) of the
field devices are connected with each other and all ”negative“ operating
voltage input terminals (–) (= reference potential) are connected together
(in-phase connection of field devices). All outputs of field devices must be
referenced to the same potential!
In case of reversed polarity at one field device, a supply voltage short-
circuit would be caused by that device. The consequential short-circuit
current flowing through this field device may cause damage to it.
Therefore, pay attention to correct wiring!
Putting in operation
After switching on the device, a self-test and tempering period follows. This procedure takes 30 - 50
minutes,depending on the ambient conditions. During this time the output analogue voltage differs from the
actual measured value.
Switching point setting
A potential-free changeover contact is available as a switch output.
A switching point between 10 % and 95 % of the measuring range can be selected using
the SET potentiometer. The 10 % value is added to the fresh air limit of 400 ppm for CO
2
.
(600...1900 ppm with MR = 0...2000 ppm or 900...4700 ppm with MR = 0...5000 ppm).
With other measurands, the corresponding lower limit is used directly as a basis.
(VOC: 10...95 %, Temperature: –23...+74 °C,
Humidity: 10...95% r.H.)
The assignment of the switch output to measurand is done via DIP switch (DIP 7 and DIP 8).
Offset
Each measuring channel has a separate offset potentiometer for subsequent adjustment of the measure-
ment. The adjusting range is ± 10 % of the measuring range.
Display
In the first and second lines, the
measurements
with the corresponding
units
( CO
2
in
ppm
, VOC in
%
, temperature in
°C
, relative humidity in
% r.H.
)
are displayed in a cyclical series.
In the third line, the
switching status of the relay
is shown on the left as a circuit
(full
●
= relay energised; empty
○
= relay de-energised)
followed by the corresponding
indicator
(
C
for CO
2
;
V
for VOC;
T
for temperature;
H
for relative humidity in
% r.H.
)
and the
switchpoint value
is shown on the right.
