KROHNE GA 24 ATEX II2G Ex i EN - Manual (Page 10)

4
ELECTRICAL CONNECTIONS
10
GA24
www.krohne.com 06/2013 - 4000836702 - MA G24-Ex-II2G-AD R03 en
Electrical connections
4.1 General notes
The electrical connection of the limit switch with protection level "ia" or "ib" is described in the
manual. Permissible maximum values (electrical data) must be observed.
Observe the specified polarities.
The TG21 limit switch is electrically connected to the connection terminals in the connection box.
The MS14 limit switch is electrically connected on the strands of the connecting cable. The
terminal compartment used must satisfy a minimum IP protection category of IP20. The MS14/A
variant is electrically connected to the connection terminals in the connection box. The MS14/
limit switch is connected regardless of polarity.
Connecting cable Connecting cable Connecting cable Connecting cable
The connecting cables must be selected according to prevailing installation standards (e.g.
EN 60079-14).. The outer diameter of the connecting cable must be within the sealing range of
the cable entry. The connecting cables must be fixed and laid in such a way as to be sufficiently
protected against damage.
All cores that are not used must be securely connected to the earth potential of the hazardous
area or carefully insulated against each other and against ground (test voltage ≥ 500 V
eff
).
4.2 Grounding and equipotential bonding
If the device is not sufficiently electrostatically grounded via the process cables, an additional
earth connection must be established using the ground terminal. The location of the earth
connection 1 on the back of the housing. This connection merely ensures electrostatic
connection of the device and does not meet the requirements for equipotential bonding.
The conductive parts of the limit switches are connected to the variable area flowmeter housing.
Ensure proper installation and fit of the installation elements.
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