I needed a mini circuit breaker panelboard to protect and segregate the loads from my solar inverter. I wanted a small form factor, transparent cover to view the breakers and adequate protection for all my house electrical loads.
I am a power system (electrical) engineer for the past 19 years to present. I have the knowledge, experience and physical skills to design, build, test and commission large (up to 132kV) power systems. DO NOT ATTEMPT WHAT I HAVE DONE IF YOU DO NOT POSSESS SIMILIAR CAPABILITIES LIKE I DO.
Electrical energy is highly dangerous and you must accept all risks when you modify any power system.
Step 1: Install Din Rail Into Enclosure and Have Cable Entry Way.
Step 2: Install the Neutral and Ground Bus Bars.
Step 3: Create and Connect the Live Bus.
Step 4: Add Led Indicators Per Sub Breaker and Incoming Supply.
Step 5: Add the ATS and AC Meter
The common of the other pole I sent to the neutral bus bar.
The NO contacts were wired to the utility live and neutral conductors. The NC contacts were wired to my solar inverter respective live and neutral. I switch both live and neutral since my inverter does not produce a grounded neutral.
The coil I wired to the utility live since in power failure I wanted the ATS to default to inverter power. I installed a toggle switch to manually select utility power in the case of inverter failure. I also put in series with the coil another relay to remotely switch between utility and inverter. This relay is part of my labjack u3 pc home controller as shown in the screen pic. Anywhere in the world I can monitor and select which power source I want plus several other parameters in my home.
An AC volt and current meter I included on the inside face of the enclosure lid. The current transformer is around the output of the ATS. As always with current transformer connections it must be tight and secure since an open circuit with cause rapid failure and blowout of the transformer.
Step 6: Commissioning and Appreciation.
I took a thermal scan and the resistor leads showed any appreciable heat. The wires from the MCBs were relatively cool.