Brochure/Catalogue

Installation advice for instrumentation and control engineering
Surge protection for sensors with 4-wire connection
or temperature measurement
The plug-in VSPC 3/4 surge protector is used to protect 3- or
4-wire measurement signals (e.g. from temperature sensors
or load cells).
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.
PE
PROTECTED
UNPROTECTED
8
10
12
2
4
6
1
3
5
7
9
11
VSPC 3/4WIRE
24 V DC
8924550000
U:28 V DC
C
I:0,45 A
N
C1 1 kA 8/20<
IP 20
U 800 V
P
≤
I
R
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.128 2028840000
Lightning and surge protection for control and instrumentation signals