ABB rec670 Commissioning Manual page 32

Section 2
Safety information
26
Always use suitable isolated test pins when measuring signals in open
circuitry. Potentially lethal voltages and currents are present.
Never connect or disconnect a wire and/or a connector to or from a
IED during normal operation. Hazardous voltages and currents are
present that may be lethal. Operation may be disrupted and IED and
measuring circuitry may be damaged.
Dangerous voltages can occur on the connectors, even though the
auxiliary voltage has been disconnected.
Always connect the IED to protective earth, regardless of the
operating conditions. This also applies to special occasions such as
bench testing, demonstrations and off-site configuration. This is class
1 equipment that shall be earthed.
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.
The IED with accessories should be mounted in a cubicle in a
restricted access area within a power station, substation or industrial
or retail environment.
1MRK 511 360-UEN A
Bay control REC670 2.1 IEC
Commissioning manual