Applications
3.2 Use as Motor Circuit Protector (MCP) for starter combinations
3VA molded case circuit breakers with UL and IEC certification
134
Manual, 01/2019, L1V30435333-01
3.2
Use as Motor Circuit Protector (MCP) for starter combinations
Molded circuit protectors for starter protection are used to protect three-phase asynchronous
motors.
Starter combinations consist of:
●
Motor circuit protectors (MCP) for starter protection
●
Contactor
●
Overload relay
In this case, the motor circuit protector provides the short-circuit protection and the
disconnector function. It is therefore equipped with an adjustable and instantaneous short-
circuit release. The contactor is responsible for operational switching of the feeder. The
overload relay provides the overload protection. These can be specially matched to the
motor.
Siemens offers two versions of the 3VA UL motor circuit protectors:
●
Magnetic trip units from the 3VA5 series in sizes 125 A and 250 A with a magnetic setting
range from 3 to 12 x I
n
●
Electronic trip units with instantaneous short-circuit protection in sizes 150 A, 250 A,
400 A and 600 A with a setting range from 3 to 15 x I
n
