Connecting a meter to my electrical circuit

I bought this thing and have no clue as to how to connect it to monitor 220v. Anyone know how these things work? I wanted to connect it to monitor all of the power usage in my shop as it has a 100 amp box.

Unfortunately that meter is really targeted for monitoring a single circuit. If you want to measure the load on the entire 100a sub-panel you would need a unit with 2 CTs(current transformers) as it needs to measure the current on each hot lead( L1 and L2) into the sub panel and sum them together.

Alternatively, you could buy a second unit( one for each hot leg) and add the current and power numbers together but that seems too much work to me😊

Yeah I found that out after reading all the questions on Amazon. I guess they do electricity different in China.