WIKA ELS Betriebsanleitung Seite 13

5. Commissioning, operation
WARNING!
Electrical connection errors of the float switches can destroy
the reed contacts. This can lead to a malfunction in the plant
and thus lead to injury to personnel or damage to equipment.
▶
No direct operation in circuits with inductive loads.
▶
No direct operation in circuits with capacitive loads, e.g.
PLC, PCS or cable lengths > 50 m.
▶
Do not exceed the permissible switching power, see
chapter 9 "Specifications".
Connection with inductive load
With inductive loads, the float switches should be protected by
connection to an RC element or a free-wheeling diode.
AC voltage
S1
R
AC 24 ... 230 V
C
RC elements for reed contacts 10 ... 40 VA
Voltage Resistance
AC 24 V 100 Ω
220 Ω
AC 48 V
AC 115 V 470 Ω
AC 230 V 1,500 Ω
Operating instructions float switch, model ELS
DC voltage
+
For RC
element
DC 24 ... 250 V
see table
–
Capacitance
0.33 μF
0.33 μF
0.33 μF
0.33 μF
S1
Type of RC element
A 3/24
A 3/48
A 3/115
A 3/230
EN
Free-
wheeling
diode, e.g.
1N4007
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