The account will be led by the agency's London team and UK MD Matt Cross, with work planned across the UK, France, Spain, Italy and the DACH region (Germany, Austria and Switzerland). Hotwire partner agencies Iteo and Yellow Communications will also collaborate on the account.
The newly created brief includes b2b and consumer comms, as well as strategy, content and local campaigns.
Cross said that the win made Eaton one of Hotwire's three biggest accounts globally. The firm has offices in Italy, Spain and two in Germany, as well as its major bases in the UK and the US.
He said: "We absolutely understand Eaton’s desire to step its comms up a gear, and feel we’re perfectly placed to bring them to market in a fresh way with our approach, working with our affiliates across the globe, as well as local offices."
Cross added that he understood Hotwire had been chosen in part due to its "expertise in telling a credible innovation story for clients", at a time when increasing numbers of firms not traditionally seen as tech companies are trying to boost their credentials in this space.
Eaton is a global firm making power management solutions that make electrical, hydraulic and mechanical power operate more efficiently, reliably, safely and sustainably. It has approximately 95,000 staff, sells its products in more than 175 countries and had 2016 sales of $19.7bn (£15.9bn).
Work started earlier this month, following a six-way pitch.
Although Hotwire's Australian parent company has said on several occasions that it has been performing well, its global CEO exited the business suddenly last week.
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