Brochure/Catalogue

Installation advice for instrumentation and control engineering
Surge protection for sensors with supply voltage and
a current loop 0 (4)...20 mA
The VSPC 1CL PW plug-in surge protector uses a
Type III arrester to protect the 24-V supply voltage and also
a D1/C2/C1-arrester for the current loop 0 (4)...20 mA.
This 17.5-mm conguration protects both power and
measurement/control (e.g. for a pumping facility).
PE
PROTECTED
UNPROTECTED
8
10
12
2
4
6
1
3
5
7
9
11
VSPC 1CLPW
24 V
8951510000
U:28 V AC
C
I:0,45 A
N
C1 <1 kA 8/20
IP 20
U 900 V
P
≤
4...20 mA
4...20mA4...20mA
PLC
4...20 mA24 V DC
24 V DC
The unprotected side points in the direction where the pulse
or interference is expected. The connecting cable’s shield
is connected to terminal 3 e. g. the Weidmüller clamping
bracket (KLBÜ) can be used.
The earthed DIN rail can then pick up the pulse and
discharge it to the earth.
For long cables, and especially for current loops, additional
protection is set-up at the sensors. The VSPC BASE FG
oating-earth base can be used there. A built-in gas
discharge tube makes this a “high impedance” earth, which
prevents an interference current on the shield.
B
B.1272028840000
Lightning and surge protection for control and instrumentation signals