Square D Homeline 200 Amp 30-Space 60-Circuit Outdoor Main Breaker Plug-On Neutral Load Center with Surge SPD - Value Pack H3060M200PRVPSG - The Home Depot

Reviews for Eaton BR 200 Amp 40-Space 50-Circuit Indoor Main Breaker Loadcenter with Cover Value Pack (3-BR120, 1-BR230) | Pg 1 - The Home Depot

Square D Homeline 125 Amp 8-Space 16-Circuit Outdoor Ringless-Horn Overhead/Underground Main Breaker CSED RC816F125CH

What Is a Main Circuit Breaker and How Does It Work?

Some HVAC Troubleshooting Tips... If you have a blown fuse or breaker, shut off the local disconnect. Replace the fuses and turn on the main or reset the breaker. Check for proper power before turning on the local disconnect. If it's present, most likely your issue isn't in the circuit between the switches. Use a megger or meter to check for ground faults or shorted loads. A visual is also good as well. I used the @supco_hvac IDVM 550 to troubleshoot this call. Looks like this one fuse may have

Circuit Breaker Tripping: Troubleshooting Guide