Shelly 1 Mini Gen4 vs Shelly 2PM Gen4

The Shelly 2PM Gen4 wins on channel count, energy monitoring, load rating and the fuller protection set, with a slightly better rating. The Shelly 1 Mini Gen4 costs much less and is the only one with dry-contact and wet-contact modes.

Channel count. The Shelly 2PM Gen4 switches two independent circuits from one module, while the Shelly 1 Mini Gen4 handles one. That decides most installations before anything else.

The Shelly 2PM Gen4, which reports consumption per channel. The Shelly 1 Mini Gen4 switches without metering.

They describe how the output is wired: dry contact gives a voltage-free switch for low-voltage gear or pulse triggers, wet contact passes mains through. Only the Shelly 1 Mini Gen4 lists both; the Shelly 2PM Gen4's are not published.

The Shelly 2PM Gen4, which adds overvoltage, overcurrent and overpower protection to the overheating protection both offer, so it fails safe under more fault conditions.

Anyone automating a single circuit in a cramped backbox for the lowest cost, or who needs dry-contact wiring for a gate, a boiler or low-voltage equipment.

Anyone with two loads in one box, such as a light and a fan, who also wants per-channel energy monitoring and the fuller set of electrical protections.