Hazardous-area soft starter with multi-protocol fieldbus
The Siemens 3RW5513-1HA14 is a soft starter carrying both ATEX and IECEx certification, meaning it is approved for installation in explosive atmospheres where gas or dust hazards are present — a requirement often specified in oil-and-gas, chemical, and grain-handling facilities. The trip class is configurable as CLASS 10A, 10E (default), 20E, or 30E per IEC 60947-4-2, which directly sets the maximum allowable motor heating during start — a CLASS 10A trip allows only 10 seconds of starting current before the overload trips, suitable for low-inertia loads like centrifugal pumps, while CLASS 30E gives 30 seconds for high-inertia loads such as crushers or centrifuges. Fieldbus integration is flexible: the unit supports PROFIBUS, Modbus RTU, Modbus TCP, and EtherNet/IP natively, so it can drop into a Siemens S7 environment or a Rockwell ControlLogix network without a separate gateway. PROFIenergy is also supported when paired with a PROFINET communication module, enabling energy-saving shutdowns during idle periods.
Panel fit and clearance planning
The enclosure dimensions are 170 mm width, 275 mm height, and 152 mm depth. For ventilation and wiring access, the required clearances are: 100 mm upward, 10 mm forward, 0 mm backward, 75 mm downward, and 5 mm at the side — the zero backward clearance means the unit can be mounted flush against a rear panel wall, saving depth in shallow enclosures. The screw terminal type is standard for panel wiring practices.
Motor control features and diagnostics
Beyond basic soft starting, the 3RW5513-1HA14 includes voltage ramp, torque control, breakaway pulse, pump ramp down, DC braking, and motor heating — the pump ramp down feature gradually reduces voltage to prevent water hammer in pumping systems, while the breakaway pulse delivers a short high-torque burst to break a stuck load free before ramping. For diagnostics, the unit provides an event list, error logbook, and trace function — the trace captures parameter trends during a fault event, which is useful for commissioning and post-incident analysis. The analog output can be configured as 4–20 mA or 0–10 V to relay motor current or torque to a PLC or panel meter. Accuracy class 5 per IEC 61557-12 applies to the measurement functions, meaning the current and voltage readings are within 5 % of the true value — adequate for protection and monitoring but not for revenue-grade metering. The service factor of 1.15 allows the motor to run at 115 % of its rated load continuously, a common requirement for pump and fan duty.
Compliance and regulatory approvals
The soft starter carries CE marking for the European market, UL approval for the United States, and CSA approval for Canada — these three approvals cover the majority of industrial installations in North America and the EU. ATEX and IECEx certification further extends acceptance into hazardous-area classified zones. Additional features include auto-reset and remote reset capability, firmware update support, and four parameterizable sets — the parameter sets allow the same unit to be configured for up to four different motors or starting profiles, which is useful for multi-motor applications where the soft starter is shared via a bypass contactor.