11
In control cabinet: Wiring the conductivity switch
Connection of supply voltage
The equipment is supplied with 24 V DC and fused with an external semi-delay fuse 0.5 A. Please use a
safety power supply unit with safe electrical isolation.
The power supply unit must be electrically isolated from dangerous contact voltages and must meet at
least the requirements on double or reinforced isolation according to one of the following standards:
DIN EN 50178, DIN EN 61010-1, DIN EN 60730-1 or DIN EN 60950.
Connecting conductivity electrode LRG 12-2, LRG 16-4, LRG 17-1 and LRG 19-1,
resistance thermometer TRG 5-..
To connect the equipment use screened multi-core control cable with a min. conductor size 0.5 mm
2
,
e. g. LiYCY 2 x 0.5 mm
2
.
Wire terminal strip in accordance with the wiring diagram.
Fig. 3
Connect the screen only once to the central earthing point (CEP) in the control cabinet.
Make sure that connecting cables leading to the equipment are segregated and run separately from
power cables.
Connecting output contacts
Wire the upper terminal strip
1
(terminals 16-23) according to the desired switching functions.
Provide an external slow-blow fuse 2.5 A for the output contacts.
When switching off inductive loads, voltage spikes are produced that may impair the operation of con-
trol and measuring systems. Connected inductive loads must be provided with suppressors such as RC
combinations as specified by the manufacturer.
When used as conductivity limiter, the conductivity switch LRS 1-50 does not interlock automatically
when readings exceed the MAX limit.
If an interlock function is required for the installation it must be provided in the follow-up circuitry
(safety circuit). The circuitry must meet the requirements of the EN 50156.
The conductivity electrode LRG 16-9 is equipped with a sensor plug-in connection type M 12, with 5
poles, A-coded, pin assignment see
Fig. 3.
For connecting the equipment preconfigured control cable
assemblies (with male and female connectors) of various lengths are available as add-on equipment.
To connect the conductivity switch LRS 1-50 remove the connector and wire the terminal strip accord-
ing to the wiring diagram.
Fig. 3.
Connect the screen only once to the central earthing point (CEP) in the control cabinet.
If you do not use the prefabricated control cable assembly, use screened five-core control cable, e. g.
LiYCY 5 x 0.5 mm
2
, for connecting the equipment. In addition, connect at the electrode end a screened
female connector to the control cable.
Make sure that connecting cables leading to the equipment are segregated and run separately from
power cables.
Connection of conductivity electrode LRG16-9
Attention
n
Do not use unused terminals as support point terminals.
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