Samsung ML-1651N - Manual (Page 166)

Precautions
DISCONNECT THE POWER CORD:
Never remove the printer control board while the printer is
plugged in.
To avoid the possibility of electrical shock, always disconnect the
power cord when installing or removing ANY internal or external
printer option.
DISCHARGE STATIC ELECTRICITY:
The control board and internal printer options (Memory DIMM,
PS DIMM, Network interface) are sensitive to static electricity.
Before installing or removing an internal option, discharge static
electricity from your body by touching something metal, such as
the metal back plate on any device plugged into a grounded
power source. If you walk round before finishing the installation,
discharge any static electricity once again.
H.1 P
RINTER
O
PTIONS