Charlie installing electrical unit in satire (7)
I believe the answer is:
lampoon
'satire' is the definition.
(I've seen this before)
'charlie installing electrical unit' is the wordplay.
'charlie' becomes 'loon' (I can't explain this - if you can you should believe this answer much more).
'installing' is an insertion indicator (inserted letters are installed).
'electrical unit' becomes 'amp' (unit of electrical current).
'loon' going around 'amp' is 'LAMPOON'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for lampoon that I've seen before include "Written ridicule of polo man" , "Satirise, ridicule" , "joke" , "Ridicule with satire" , "send-up" .)