A sailor keeping power right on standard setting (2,3)

I believe the answer is:
at par
'right on standard setting' is the definition.
I know nothing about this answer so I cannot judge whether this works.
'a sailor keeping power' is the wordplay.
'sailor' becomes 'tar' (term for a sailor).
'keeping' indicates putting letters inside (some letters kept inside).
'power' becomes 'p' (symbol in physics).
'tar' placed around 'p' is 'tpar'.
'a'+'tpar'='AT PAR'
Can you help me to learn more?
(Other definitions for at par that I've seen before include "for what it's worth" , "for original cost" .)
