Tesla TI2000GPU-24 - Manual (Page 6)

Guard from incorrect power source
1-2
1-6. FORMS AND RECORDS
NONE REQUIRED.
1-7. USE OF WORDS SHALL, SHOULD, AND MAY.
Within this technical manual the word “shall” is used to indicate a
mandatory requirement for proper operation and warranty purposes.
The word “should” is used to indicate a non-mandatory but preferred
method of accomplishment. The word “may” is used to indicate an ac-
ceptable method of accomplishment.