KROHNE SMARTSENS ORP 8150 Ex EN - Manual (Page 12)

4
ELECTRICAL CONNECTIONS
12
SMARTSENS ORP 8150
www.krohne.com 07/2014 - 4003048502 - MA SMARTSENS ORP 8150 R02 en
4.4 Grounding and equipotential bonding
To dissipate dangerous electrostatic charges the metal housing must be grounded. The shield of
the sensor cable must be connected to the ground potential. The electrical connection to the
metal housing and the grounding is made through the sensor cable with the VP connector.
When using junction box type SJB 200 W-Ex, the shield of the sensor cable must be connected to
the shield connector provided. This will ensure sufficient electrostatic grounding and at the
same time prevent unacceptably high equalizing currents.
WARNING!
The cable shield must not be connected directly on both ends to the ground potential, since
unacceptably high equalizing currents can flow at potential differences.
INFORMATION!
On junction box type SJB 200 W-Ex, the shield connector is connected to the ground potential via
a 1 megohm resistor and a capacitor in parallel.
The connections for the intrinsically safe 4...20 mA sensor circuit are galvanically isolated from
both the electrode circuit and the ground and can be considered ungrounded (test voltage
500V
eff
). It is accepted that the electrode circuit can be directly connected to the ground
potential.
.book Page 12 Friday, July 11, 2014 2:56 PM