Wiring Connections
General Information
Load Limit Values
Note the limit values of the loads to
which you want to connect the
Nivocompact. Exceeding the load can
destroy the electronic insert (or the relay
contact in the EC 24).
Fuse
Ensure that the rating of the fine-wire
fuse corresponds to the maximum load
to be connected;
the fine-wire fuse does not protect the
electronic insert of the Nivocompact
FTC.
Diameter of Wiring
Because of the small currents used,
only small diameter cabling is required.
Low-cost cabling with diameters of
0.5 mm
2
to max. 1.5 mm
2
is
recommended.
Grounding
The Nivocompact must be grounded to
give reliable operation free from
interference. This is done by either
connecting it to a grounded silo with
metal or reinforced concrete walls or
else to the earth conductor PE.
If a counter electrode is connected to a
silo made of plastic material then there
must be a short ground connection from
the Nivocompact to the counter
electrode.
Connecting the Nivocompact
with Electronic Insert EC 20
for AC Voltage
(Two-Wire Connection)
Connecting in series to a load
The level limit switch Nivocompact with
electronic insert EC 20 must - like all
switches - be connected in series with
the load (e.g. relays, microcontactors,
lamps) to the power supply.
Connection voltage
The voltage across Terminal 1 and 2
of the electronic insert must be at least
21 V.
The power voltage must be
correspondingly higher to compensate
for the voltage drop across the
connected load.
Load cutoff
Note that loads connected in series are
not completely disconnected from the
power supply if the electronic switch in
the electronic insert of the Nivocompact
»cuts off« (blocks) with the level alarm.
Because of the current requirements of
the electronics, a small »residual
current« still flows through the external
load.
When the load is a relay with a very
small retaining current, then the relay
may not de-energise. In this case
connect an additional load in parallel to
the relay, e.g. a resistor or signal lamp.
TI133Y14
EC 20
1
2
M
E
U
1-2
∼
R
F
U
R
L1
N
PE
Power supply
U
∼
: min. 21 V + U
R
max. 250 V
Connecting the
Nivocompact with
EC 20 electronic insert
U
1-2
∼
: 21 V
…
250 V
across Terminals 1
and 2 of the EC 20
R: Connected
(external) load ;
e.g. relay
F: Fine-wire fuse,
load-dependent
M: Ground connection
to silo or to counter
electrode
E: Grounding
U
R
: Voltage drop
between the load
R and the fine-wire
fuse
Connecting the EC 20
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