En
gl
is
h (
G
B)
12
8.2 Relay outputs
With inductive loads (also relays and contactors),
interference suppression is necessary. If this is not
possible, protect the relay contacts using a
suppressor circuit as described below.
•
With AC voltage:
•
With DC voltage: Connect free-wheeling diode in
parallel to relay or contactor.
Fig. 7
Suppressor circuit, DC/AC
8.3 Current output
The current output can be set to the two standard
ranges, "0 to 20 mA" or "4 to 20 mA".
Connect all screens at one end to the screen earth
(terminal 15).
Current output
The current output outputs the displayed measured
value as an analog current signal with respect to the
measuring range.
Use of current signal
Use the current signal as input signal for an
additional display unit.
8.4 Connections for water sensor and
temperature sensor
Connection of water sensor
•
A sensor (NAMUR switch) is used for the
AQC-D1/-D11/-D2/-D12/-D3 and AQC-D13
measuring cells. For cable colours and
designations, see section
.
Connection of Pt100 temperature sensor
(Conex
®
DIS-PR)
1. Connect "+" conductor to terminal 17.
2. Connect "-" conductor to terminal 18.
Note
The connection of the relay outputs
depends on the application as well as the
device controlled. Therefore the
connections described below should only
be considered as guidelines.
Current up to
Capacitor, C
Resistor, R
60 mA
10 nF, 275 V
390
Ω
, 2 W
70 mA
47 nF, 275 V
22
Ω
, 2 W
150 mA
100 nF, 275 V
47
Ω
, 2 W
1.0 A
220 nF, 275 V
47
Ω
, 2 W
Caution
Provide the relay outputs with a
corresponding backup fuse!
TM
03
72
09
28
13
+
-
DC
R
C
AC
Caution
Make sure that the polarity of the current
output is correct! Maximum load: 500
Ω
.
Caution
When using the AquaCell AQC-D2/-D12
measuring cell, the water sensor must
always be connected and activated!