The Siemens 3VA1110-5EE32-0AG0 is a SENTRON molded case circuit breaker (MCCB) sized for line protection in a 3-pole, 100 A frame. It carries a TM220 thermal-magnetic release — that means the thermal element handles overloads and the magnetic element handles short circuits, no electronic adjustments on this variant. The 187 kA breaking capacity at 240 V AC tells you it can interrupt a serious fault without the arc climbing into the buswork; at 415 V AC it still holds 121 kA.
What the ratings mean on the panel
At 40 °C ambient this breaker carries a full 100 A continuous without derating. Push the ambient to 55 °C and it still holds 98 A; at 70 °C it's 91 A. That derating curve matters when you're packing breakers tight in a warm enclosure — the thermal trip element responds to the heat in the breaker body, so a hot panel reduces the headroom. The rated insulation voltage is 800 V, which covers 480 V and 600 V class systems with margin. The 3VA1110-5EE32-0AG0 is designed for line protection — it's the main or feeder breaker in a distribution panel, not a motor-protective device. It comes with one auxiliary switch and one trip alarm switch built in, so you can wire a remote status signal back to a PLC or annunciator without adding an external accessory block. The trip indicator on the front gives a quick visual on whether it tripped on fault or was manually opened — useful for a field tech walking a lineup.