DC Polarity Switching Box with Remote Control - Arduino

I am in need of a specialist capable of building a DC polarity switching box, capable of functioning input of at least 100V 30A DC. Needs to allow operations to be manually conducted, as well as run via computer remotely. Here's what you might need to know:

- Manual Operation: The box should be equipped to switch between positive, off, and negative polarity.
- Computer-Driven Operation: In terms of computer operation, the system absolutely needs to be capable of real-time polarity adjustment with reporting of current.
- Connectivity: The device should have a modem or SIM card functions for remote control in a very remote location (ie. a forest running on a generator)
- Security: To safeguard against unauthorized access, the system should have a basic PIN or password protection mechanism in place.

Ideal freelancers for this project would be those with background and experience in electrical engineering, hardware design, and system security. The ability to suggest and implement effective measures for the real-time polarity adjustment feature would be a bonus. If you're an expert who can integrate these functionalities into one robust system, then I'd be excited to get started with you.