Compact and Capable Motor Control with Gefran G-Start

Gefran recently released one of the smallest all-digital motor control packages yet. Called the G-Start, these controllers offer all of the features that one could expect on a motor controller, all placed into a package that is DIN-rail mountable.

This controller is not considered a VFD or a soft starter, since it does not handle speed control. In that sense, its behavior is more like a motor contactor packed with a host of additional features. Digital inputs and outputs allow various control schemes, while built-in monitors evaluate the current, phase balance, and any present alarms.

“Compared to the mixed use of contactors and motor protections usually found in the control of three phase motors, G-Start reaches the same results with a device of just 22.5 mm in width,” says Paolo Buzzi, Controllers and Power Controllers Marketing Manager at Gefram.

 

The G-Start motor controller. Image used courtesy of Gefran

 

G-Start Features

Each G-Start motor controller is equipped with four basic functions: direct and reverse motor start, thermal protection, and diagnostics. Many motor controllers require separate modules for thermal protection and diagnostics (like an OL relay), but these are built right into the G-Start series controllers. Also, each controller is equipped with SIL-3 emergency stop capabilities, such that the motor can be stopped without the need for a separate emergency stop system.

The G-Start series is available in both single-phase and three-phase arrangements, although the reversing function is only available on the three-phase variants. The controllers are available in adjustable 0.6 A, 2.4 A, or 7.0 A output current models. The compact size of these motor controllers allows them to be placed near other process equipment, where other motor controllers may not fit. Measuring only 115 mm x 136 mm x 22.5 mm, they are perhaps some of the smallest motor controllers on the market.

 

A CAD drawing shows the I/O wiring connections along the top side of the G-Start motor controller. Image used courtesy of Gefran

 

What makes the G-Start controllers unique is all of the protection and on-board diagnostics available in the controller. Many controllers require external protective devices and diagnostic sensors, but this is not the case with the G-Start controllers.

Motor controllers must not only have overcurrent protection, but must include thermal protection. Consider the situation where a motor is running near stall conditions due to worn bearings, dust accumulation, or other issues. The current draw may not be high enough to trip the overcurrent protection, but it might be enough to gradually heat up the motor and other hardware beyond safe limits. Current protection devices must be set at a high initial rating to prevent tripping during startup due to high inrush current. Additional thermal protection prevents the system from long-term overheating, even if the current protective device is not triggered.

 

Potential Markets

Gefran expects these motors to be used on compressors, mixers, loading hoppers, compressors, fans, pumps, blowers, and other materials handling and cooling equipment. Also, because the G-Start motor controllers can reverse directions, they can also be used for rolling operations, conveyor belts, and others that might require a backtracking step.

 

The Future with G-Start

The compact design and the ability to quickly install and run the G-Start motor controllers is a tremendous advantage. These small controllers are anticipated to find use in automation systems where space is limited. Furthermore, the simplicity of troubleshooting these modules makes them a good choice for training new technicians on motor control basics, industrial wiring practices, and other such topics.