ABB Relion 670 series, Installation And Commissioning Manual

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Never disconnect the secondary connection of current transformer
circuit without short-circuiting the transformer’s secondary
winding. Operating a current transformer with the secondary
winding open will cause a massive potential build-up that may
damage the transformer and may cause injuries to humans.
Never remove any screw from a powered IED or from a IED
connected to powered circuitry. Potentially lethal voltages and
currents are present.
Take adequate measures to protect the eyes. Never look into the
laser beam.
2.2 Caution signs
Always transport PCBs (modules) using certified conductive bags.
Always handle modules using a conductive wrist strap connected to
protective ground and on a suitable antistatic surface. Electrostatic
discharge (ESD) may cause damage to the module since electronic
circuits are sensitive to this phenomena.
Do not connect live wires to the IED. Internal circuitry may be
damaged
Always use a conductive wrist strap connected to protective ground
when replacing modules. Electrostatic discharge (ESD) may
damage the module and IED circuitry.
Take care to avoid electrical shock if accessing wiring and
connection IEDs when installing and commissioning.
Changing the active setting group will inevitably change the IEDs
operation. Be careful and check regulations before making the
change.
Section 2
1MRK 502 029-UEN A
Safety information
16
Installation and commissioning manual