What this MCCB is and what it does
The Siemens 3VA2110-5HL36-0AJ0 is a SENTRON molded case circuit breaker (MCCB) rated for line protection in three-phase distribution. It carries a rated continuous current Iu of 100 A and is built around the ETU320 electronic trip unit, which provides adjustable overload and short-circuit protection curves. Breaking capacity is the headline spec here: 187 kA at 240 V, 121 kA at 415 V and 440 V, 79 kA at 500 V, and 4.25 kA at 690 V. That 187 kA at 240 V tells you this breaker is sized for high-fault-current points in the distribution — main incomers or large feeder breakers where available fault current is substantial. The 100 A rating holds steady from 40 °C through 50 °C, then derates to 96.25 A at 55 °C, 92.5 A at 60 °C, 88.75 A at 65 °C, and 85 A at 70 °C. If the panel ambient runs above 50 °C, the continuous load must be trimmed per that curve — the 85 A figure at 70 °C is the floor. Rated insulation voltage Ui is 800 V, and the unit carries IP40 protection on the front — suitable for enclosed panel mounting where the front face is behind a door or cover. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.
Trip unit and auxiliary contacts
The ETU320 is an electronic overcurrent release with no undervoltage release, no voltage trigger, no phase failure detection, and no communication function — it is a standalone thermal-magnetic replacement with adjustable trip settings. The breaker includes 2 auxiliary switches plus 1 trip alarm switch (HP version), giving three discrete signals for status feedback to a PLC or panel indicator. Mechanical endurance is rated at 20,000 operations — typical for an MCCB in a distribution role where it sees infrequent switching. Maximum power loss is 10 W, which factors into thermal management inside a sealed enclosure.
Dimensions and panel fit
The 3VA2110-5HL36-0AJ0 measures 86 mm deep, 105 mm wide, and 181 mm tall — a 3-pole MCCB footprint that fits standard Siemens 3VA panel cutouts and busbar arrangements. The 105 mm width is the critical dimension for multi-pole grouping in a distribution board.