Crossword Genius

Very happy about copper rod for electrical component (7,6)

Ross

I believe the answer is:

mercury switch

I'm a little stuck... Click here to teach me more about this clue!

'electrical component' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'very happy about copper rod' is the wordplay.
'very happy about copper' becomes 'mercury' (I can't justify this - if you can you should believe this answer much more).
'rod' becomes 'switch' (I've seen this before).
'mercury'+'switch'='MERCURY SWITCH'

'for' acts as a link.

Can you help me to learn more?

(Another definition for mercury switch that I've seen is " one's tipped on and off".)

I've seen this clue in The Times.
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