Grounding - ABB LWT300 Series User Manual

ELECTROSTATIC DISCHARGES
Before performing any connection, operators shall make sure that they have discharged all
static electricity from their body before touching electronic components.
• All connections must be established in a de-energized state.
• Before installing the instrument, make sure that the appropriate supply voltage is available.
• The power supply shall be equipped with short circuit protection and auto restart functions.
• For continuous installation protection, a double insulation power supply (5 kV or higher) shall be
used for the supply and communication lines.
• In an industrial environment where EMIs (electromagnetic interferences) are extremely present (e.g.,
rock quarries, mines, large chemical plants, etc.), ABB recommends the use of noise filters on the DC
power supply to the instrument.
• Instruments will not work if exposed to common mode voltages in excess of the maximum allowed
supply voltage.

Grounding

• Ground the instrument according to requirements (see "Grounding the instrument" on page 27).
WARNING
Ensure that the equipment or any device or power cord connected to the instrument is
properly grounded.
If an interruption of the protective earthing connection is suspected, make sure that the
equipment is not used. All protective earthing connections (grounding) must be active at
all times. The absence of grounding can lead to a potential shock hazard that could result
in serious personal injury.
Use the instrument only if a properly grounded power source is available in accordance
with the local electrical code.
• To avoid injury or property damage in external installations exposed to lightning, a transient voltage
suppression module or galvanic isolator shall be installed, with proper grounding, before entering a
building with a cable. Refer to local building and electrical codes for proper practices.
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User Guide