Commissioning engineer's note
The Siemens SENTRON 3VA1120-3EF36-0CA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, fitted with a TM240 thermal-magnetic overcurrent release. The TM240 trip unit is fixed — no interchangeable trip blocks — so the breaker's continuous current rating is determined by the release: 20 A through 55 °C, derating to 19 A at 60–70 °C. Breaking capacity at 240 V is 75.6 kA, dropping to 52.5 kA at 415 V and 32 kA at 440 V; at 500 V and 690 V it holds at 11.9 kA. The unit includes an undervoltage release (UVR) as standard, wired separately. No ground-fault monitoring, no communication module — this is a straightforward line-protection breaker for distribution panels.
Mounting and integration
Dimensions: 130 mm height, 76.2 mm width, 70 mm depth. Mounts on DIN rail or panel. The 3-pole footprint matches standard SENTRON 3VA1 family cutouts. The UVR coil terminals are on the left side; verify free-wheel diode polarity on the control circuit before energizing. No auxiliary contacts are included — order separately if remote status is needed. Power dissipation at rated load is 14.5 W max; allow airflow in the enclosure to avoid cumulative heat rise above 70 °C operating limit.
Delta: 3VA1020-3ED36-0AA0
The closest functional sibling is the 3VA1020-3ED36-0AA0. Both are 3-pole SENTRON MCCBs with TM releases and UVR. The 3VA1020 frame has a lower interrupting rating — typically 25 kA at 415 V vs. this unit's 52.5 kA — and a different trip curve (ED vs. EF). Physically, the 3VA1120 is 76.2 mm wide vs. the 3VA1020's 70 mm; check panel cutout compatibility before swapping.