IBM N6270 Hardware And Service Manual page 4

A general danger notice provides instructions on how to avoid shock hazards
when servicing equipment. Unless instructed otherwise, follow the procedures in
the following danger notice.
iv
IBM System Storage: N6200 Series Hardware and Service Guide
DANGER
An electrical outlet that is not correctly wired could place hazardous
voltage on metal parts of the system or the devices that attach to the
system. It is the responsibility of the customer to ensure that the
outlet is correctly wired and grounded to prevent an electrical shock.
(D004)