User Manual

22 Capacitive electrodes EK 4 … 20 mA - Compact
22574-EN-020809
Electrical connection
A
B
2
1
E2
E1
A2
A1
2
1
A2
A1
E2
E1
Vessel with cathodic corrosion protection
(Ex) area Zone1
Non (Ex) area
Overvoltage
protection unit
mounted to
oscillator
Oscillator
b)Capacitive electrodes with external
overvoltage protection unit
Schirm
Cathodic tank protection
2 … 24 V (object voltage)
CB
2-36
CAP
E32(H)EX
External ground terminal
Internal ground terminal
Vessel
Zone 0
Li, Ci of the oscillator with overvoltage
protection unit
Li = 0.27 mH
Ci = 8.5 nF
Control room
optionally:
Overvoltage
protection insert
Signal
condit-
ioning
instru-
ment
or
safety
bar-
rier
Type B62-36G
Li=0.15 mH
Ci=2.5 nF
Overvoltage protection unit
Overvoltage arrester in
metal housing or in plastic
housing must be installed
earth-free
External ground terminal
Internal ground terminal
Cathodic tank protection
2 … 24 V (object voltage)
Insulated cable
min. 4 mm
2
Vessel
Zone 0
Oscillator
Li=0.12 mH
Ci=6 nF
Screen
CAP
E32
(H)Ex
Typ
B62-36G
Li=0.15 mH
Ci=2.5 nF
A suitable cable, if necessary with metal cover or
screen, must be used between control room and
overvoltage protection system. Metal cover or
screen - if necessary - should only be connected to
the electrode side of the overvoltage protection
system. The cable must have an outer insulation.
Test voltage of cable A: • 500 V AC
A suitable cable with metal cover, screen or a
suitable cable in a protective metal tube must be
used between overvoltage protection system and
capacitive electrode (metal cover or protective
tube must not be earthed)
Test voltage of cable B: • 1500 V AC
a)Capacitive electrodes with integrated
overvoltage protection unit type CB 2-36
A
B