ABB REB500 Operation Manual page 8

National and local electrical safety regulations must always be
followed.
The frame of the IED has to be carefully earthed.
Whenever changes are made in the IED, measures should be taken
to avoid inadvertent tripping.
The IED contains components which are sensitive to electrostatic
discharge. Unnecessary touching of electronic components must
therefore be avoided.
Take care never to open the secondary circuits of CTs conducting
current.
There is a danger of contact with live parts when opening REB500
cubicle doors.
Electrostatic discharge can destroy components in the equipment.
Other safety instructions pertaining to particular operations are
contained in the respective chapters of the operating instructions.