Dell PowerConnect RPS-60 Guide D'installation page 22

Polish Center for Testing and Certification Notice
The equipment should draw power from a socket with an attached
protection circuit (a 3-prong socket). All equipment that works together
(computer, monitor, printer, and so on) should have the same power supply
source.
The phasing conductor of the room's electrical installation should have a
reserve short-circuit protection device in the form of a fuse with a nominal
value no larger than 16 amperes (A).
To completely switch off the equipment, the power supply cable must be
removed from the power supply socket, which should be located near the
equipment and easily accessible.
A protection mark "B" confirms that the equipment is in compliance with
the protection usage requirements of standards PN-93/T-42107 and
PN-EN 55022: 1996.
21
D e l l Po w e r C o n n e c t R P S - 6 0 S e t u p G u i d e