What this MCCB carries and where it fits
The Siemens SENTRON 3VA1112-4EF32-0CH0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection — the core job is protecting feeders and downstream distribution from overloads and short circuits. Its TM240 thermal-magnetic release gives a 125 A continuous current rating across a 40 °C to 50 °C ambient, then derates to 112.5 A at 70 °C (–). The interrupting capacity hits 121 kA at 240 V AC, 75.6 kA at 415 V, and still holds 11.9 kA at 690 V (–) — that's serious fault-clearing headroom for a 125 A frame. Rated insulation voltage Ui is 800 V. The front carries IP40 protection, so it's panel-mount only, not for washdown zones.
Auxiliaries and release options
This MCCB ships with an undervoltage release (UVR) built in — it trips the breaker when control voltage drops below a threshold, standard for safety circuits that need a loss-of-voltage disconnect. The auxiliary contact block is a 2-auxiliary-switch plus 1-trip-alarm-switch HQ configuration, giving three independent signal paths for remote status. The integrated auxiliary trip uses order code 3VA9608-0BB24 — that's the specific accessory part if you're replacing or stocking spares.
Panel fit and dimensions
Dimensions are 130 mm height, 76.2 mm width, 70 mm depth. The 76.2 mm width is a standard 3-pole MCCB footprint — it fits the same DIN-rail or panel-mount cutout as other SENTRON 3VA frames. The 70 mm depth is shallow enough for most 200 mm deep enclosures without crowding the door clearance. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Latching endurance is rated at 15,000 operations — that's the mechanical life for the switching mechanism under normal use.