erc-server-reconnect-attempts

erc-server-reconnect-attempts is a variable defined in `erc-backend.el'.
Its value is

2

Documentation:
The number of times that ERC will attempt to reestablish a
broken connection, or t to always attempt to reconnect.

This only has an effect if `erc-server-auto-reconnect' is non-nil.

You can customize this variable.