Hi,
To ask for general advice, it would help the community to help you if you gave some basic requirements.
- Where are you?
The photo shows kit labelled form Toronto, Canadia
, but assumptions with power engineering kill. 
- What voltage/ current/ regulation?
I am an Electrical Engineer and know some of BS7671 for UK 230V 50Hz, but no idea about left-pondians. - What are you trying to do?
This is the most important question.- High current contactors are available to control loads, but without proper sizing, surge/ over current/ startup interlocks/protection these can cause a safety issue.
- Most folk are more interested in energy usage than control of primary circuits.
A current transformer and the local equivalent of a Shelly EM work well here, but there are recent YouTube videos from the like of Rob at “The Hook Up” on whole-home power monitoring in the US.
- What is your skill level?
Frankly, if you are starting out, don’t start with high current circuits that can burn your house down, and invalidate insurance, and local building controls.
My suggestion is if you are looking at more than energy monitoring, you need a locally certified Electrical Engineer - but I don’t know a thing about your local laws, and am trying to help safely.
If this helps, 
this post!