What it is and what it does
The Siemens 3VA1110-5MH32-0CC0 is a 3-pole IEC frame 160 molded case circuit breaker rated for starter protection. It carries a 100 A thermal-magnetic trip unit (TM120M) with adjustable magnetic short-circuit release set from 5 to 15 times In. The interrupting rating hits 55 kA at 415 V AC (breaking capacity class M), which means it can clear a fault up to that level without upstream damage — sized for high-fault industrial distribution panels where the available short-circuit current is substantial.
Key ratings and what they mean for fit
The 55 kA Icu at 415 V is the headline number — that is the ultimate breaking capacity, the maximum fault the breaker can interrupt once and still be functional afterward. For a 100 A frame, that is a high interrupting rating, typical of a 'M' (medium) class in the 3VA1 family. The TM120M trip unit provides thermal-magnetic protection: the thermal element handles overloads (though this variant ships without overload protection — the TM120M is configured for short-circuit only), and the magnetic element handles instantaneous short-circuit trips. The adjustable Ii range (5–15 x In) lets you coordinate with downstream devices; set it low for sensitive loads or high for motor inrush.
Deployment context and integration
This breaker mounts in a standard IEC frame 160 footprint — panel builders will find it fits the same DIN-rail or screw-mount pattern as other 3VA1 units. The nut keeper kit is included, which simplifies panel assembly by holding the mounting nuts in place during installation. The undervoltage release (UVR) operates on 120–127 V AC, 50/60 Hz; it trips the breaker when control voltage drops below about 70% of rated, which is standard for safety circuits that need to drop power on loss of control supply. Two auxiliary switches (HQ type) provide status feedback — one for the main contacts, one for the UVR or alarm state.