SENTRON 3VA2 MCCB — motor protection with ETU350M
The Siemens 3VA2163-5MN36-0BA0 is a 3-pole molded case circuit breaker (MCCB) from the SENTRON 3VA2 series, configured as a motor protection device. It carries a rated continuous current Iu of 63 A and a rated insulation voltage Ui of 800 V. The overcurrent release is an ETU350M electronic unit, which provides adjustable protection curves suitable for motor starting profiles. Breaking capacity reaches 187 kA at 240 V, 121 kA at 415 V, and 75.6 kA at 500 V — figures that give substantial SCCR headroom for most industrial distribution panels.
Current derating and thermal limits
The unit holds full 63 A rating up to 50 °C ambient. Above that, derating is gradual: 60.48 A at 55 °C, 59.22 A at 60 °C, 57.96 A at 65 °C, and 56.7 A at 70 °C. Maximum power loss is 75 W. For a panel builder, this means the breaker can be grouped in a standard enclosure without forced ventilation at typical 40 °C ambient, but if the panel is located near a heat source or in a non-climate-controlled area, the derating curve must be applied to the connected load.
Protection and auxiliary functions
This MCCB includes an undervoltage release (UVR) as the auxiliary release design — it will trip the breaker if supply voltage drops below a threshold, protecting motors from restarting unexpectedly after a brownout. Phase failure detection is integrated, so the breaker will open on loss of one phase, preventing single-phasing damage to three-phase motor loads. The supplied basic switch is order code 3VA2163-5MN36-0AA0, and the integrated auxiliary trip is 3VA9608-0BB11. No auxiliary contact version is fitted as standard.
Mechanical endurance and environmental range
Rated for 20,000 latching operations. Operating temperature range is -25 °C to 70 °C; storage range extends from -40 °C to 80 °C. Dimensions are 86 mm depth, 105 mm width, and 181 mm height — the 105 mm width is standard for a 3-pole MCCB in this class, fitting most panel-mounted or DIN-rail adapters.