Smart motor starters, multifunctional motor starters

Many functions and high space saving as well as expandable

Narrow width of only 22.5 mm

Demanding drive tasks require powerful and flexible device solutions. The smart motor starters of the MINISTART series combine several functions in a compact device with a width of only 22.5 mm. The combination of motor control and monitoring functions means, for example, that conventional direct-on-line starters or conventional reversing starters can be dispensed with. This saves the user material costs, time for device connection and commissioning, as well as space and wiring requirements in the control cabinet.

The following functions can be monitored or switched, depending on the motor starter variants:

Multiple functions in one motor starter

	Turning (counterclockwise / clockwise) Clockwise and counterclockwise rotation can be selected via control inputs or Modbus RTU. The direction of rotation is reversed without wear by semiconductor elements and motor-protecting by integrated soft start function.
	Soft start / soft stop The drive can start/stop without jerks and the drive elements are not damaged, i.e. maximum protection for mains, motor and machine.
	Phase failure In order not to load the motor with asymmetrical currents, it is checked at motor start whether the phases L1, L2, L3 are present.
	Phase sequence monitoring The phase sequence monitoring checks the direction of rotation of the phase voltage after switching on and signals an error in the case of a counterclockwise rotating field.
	Motor protection Comfortable protection by the electronic motor protection relay with automatic and remote reset function.
	IE3 ready Gentle operation of three-phase motors in efficiency classes IE1, IE2 and IE3.
	Current monitoring The motor current is monitored to ensure blocking protection. The switching threshold is adjustable. This provides permanent protection of the motor and machine against overload.
	Galvanic mains isolation In the idle or fault state of the motor, the motor connection terminals are isolated from the mains voltage via a 3-pole, positively driven relay.

Easy expansion for multi-motor applications

In addition, subsequent expansions can be easily planned and implemented. For example, in multi-motor applications, the motor starters already present in the control cabinet can be easily and cost-effectively expanded with additional smart motor starters thanks to their minimal enclosure width.

Networking with the Modbus RTU interface

Monitoring, switching, control and diagnostics with Modbus

Commissioning, parameterization and monitoring is simple and fast via the Modbus RTU interface. The fieldbus connection saves wiring and offers extensive diagnostic options that increase the system's reliability and availability. The simple integration of Modbus RTU is ideal for multi-motor applications, such as those usually found in wood heating systems for pellets or wood chips. A space-saving design of the power supply is possible due to a common fuse protection of all motor outlets with one circuit breaker and uniform cable cross sections. Likewise, all drives are controlled directly centrally via a Modbus RTU fieldbus line, eliminating the need for complex wiring.

Durable and energy-efficient - hybrid switching technology perfectly combined

Robust relay technology combined with wear-free solid-state technology

The internal relay provides galvanic mains isolation of the power outputs. While a semiconductor control ensures smooth motor run-up, the direction of rotation is reversed by relay switching. The hybrid relay thus combines the advantages of robust relay technology with wear-free solid-state technology. The user benefits from a significantly longer device service life and reliability. With the integrated current monitoring as overload or blocking protection, the system availability is further increased.

Phase inverter with automatic rotating field correction

Automatic correction of the direction of rotation

The motor starters or phase inverters enable reliable starting of asynchronous motors and ensure that a clockwise rotating field is always applied to the motor when it is connected to the mains and that the motor runs correctly at the first attempt. The device automatically corrects the rotating field if the mains connection is incorrect, thus preventing the motor from running backwards and being damaged.

The phase inverter is suitable for applications in which equipment is connected to the mains at changing locations, especially for mobile machines such as pumps, blowers, grinders and compressors, as well as for use by fire departments or technical relief organizations. Whether retrofit or initial equipment, the phase inverter can be used in a space-saving manner and always ensures the correct direction of rotation. Troubleshooting or rewiring is therefore no longer necessary.

Integrated motor protection functions of the motor starter

Convenient protection thanks to the electronic motor protection relay

Due to the integrated motor protection function, separate motor protection switches can be omitted. A circuit breaker provides line and short-circuit protection for the entire system.

Are you looking for wear-free solid state technology with or without heat sinks?

The solid state relays from Dold are characterized by wear-free and noiseless switching of currents. Due to the long service life, you are spared a cost- and time-intensive device replacement. The device can be mounted on existing cooling surfaces. Optionally, the solid-state relays are also available with an appropriately pre-dimensioned heat sink (with additional heat sink called solid-state contactor), which allows a quick and easy commissioning.