Ohmline builds the controller inside a substation: the box that opens and closes breakers, reads the meters and reports to the control room. Most of the ones in service cannot be updated without a crew, a truck and a permit, and so most of them never are.

Carl Brzezinski designed protection relays for fourteen years. Aisha Mbeki spent a decade in utility cybersecurity. The Ohmline controller accepts a signed update, applies it in a window the utility picks, and rolls back by itself if the readings go wrong. Every action is logged where an auditor can read it.

The company is installed at 38 substations across four utilities and a handful of cooperatives, and it ships on a schedule that the utilities’ own engineers set. Renewals have mostly been a short email. The next product is a version for the feeder level.