(2) A person who contravenes subsection (1) commits an offence, and is liable, on conviction
(a) for a contravention of subsection (1) (c) or (d), to a fine of not more than $500, and
(b) for a contravention of subsection (1) (a) or (b), to a fine of at least the amount prescribed by the regulations but not more than $500 and, in addition, to a penalty of at least the amount prescribed by the regulations but not more than $6 for every 45 kg of overload,
and every contravention constitutes a separate offence.