Space-saving Motor Starter with Additional Functions
- Published: Tuesday, 13 November 2012 15:10
Wöhner, world-wide renowned for its busbar system technology as well as electromechanical components for control system construction, energy distribution and renewable energies has expanded its portfolio with the addition of motor starters.
The two market managers at Wöhner, Hubert Lenker and Mario Engelhardt, answer some questions about the features of the motor starters, where they fit in the product range and about the philosophy behind them.
Why have you extended the busbar system technology with the “MOTUS ContactronControl”?
H. Lenker: The busbar system technology has undergone continuous further development in recent years. Tried and tested solutions are now available for a wide range of applications, both for fuses and for electromechanical switchgear. This technology has also been increasingly used around the world for many years.
The innovative combination of electronics and busbars is opening up whole new perspectives. We want to offer our customers these synergies. The benefits range from increased security to energy efficiency and from space-savings to effective operation of the systems. Together with Phoenix Contact Electronics, our strong partner in the field of industrial electronics, we have taken the first step in this direction by developing the motor starter “MOTUS ContactronControl” on the basis of hybrid technology.
Wöhner never had its own motor starter or motor circuit breaker in its product range.
M. Engelhardt: We used to mount the motor starter combinations or the circuit breakers of leading manufacturers onto the busbars using our “EQUES” adapter. Many switchgear manufacturers have for many years also been using our adapters for their own applications.
We are now able to fulfil the longstanding wish of users to connect switchgear and busbars directly, as in the case of busbar mounting fuses. With the development of the “MOTUS ContactronControl”, we are taking another step towards implementing our vision of making busbar systems more intelligent.
What power range do the motor starters cover, and what do you see them being used for?
H. Lenker: Just three versions of the “MOTUS ContactronControl” enable extremely fine setting of the motor current in the 0.075A to 9.0A range. For conventional motor circuit breakers, more than 16 variants are needed.
The “MOTUS ContactronControl”, similar to a reversing contactor combination, fulfils both directions of rotation – forward and reverse rotation. In addition, the device comes with integrated motor overload protection, which protects the motor against impermissible overloads. In addition to these three functions, the integrated safety function enables use in safety-related applications. With this in mind, we are looking specifically at applications in those areas in which small drives have to perform alternating rotations, such as actuators and conveying and pumping systems.
What exactly makes these applications ideal areas in which to use the new motor starter?
H. Lenker: Due to a change in standards, the concepts for functional safety have to be revised for many applications. The arrangement of multiple independent interruptions in each circuit and the provision of additional measures enables safety category 3 with performance level “e” to be achieved. The devices have a self-diagnostic feature that accurately recognises internal errors and rules out any malfunction. In extreme fault causes, the integrated fuses provide additional protection. After replacing the fuses, the device is ready to use again. Coordination type 2 is achieved with this protection.
“The integration of four functions – forward, reverse, motor overload protection and Emergency Stop – in just one device negates the need for additional wiring."
Compared to normal reversing starter combinations, the space required can be reduced by up to 75% with the “MOTUS ContactronControl”
What distinguishes the “MOTUS ContactronControl” from other motor starters?
M. Engelhardt: There are three main features. Firstly, the “MOTUS ContactronControl” is only 22.5mm wide. Comparable reversing starter combinations normally need 90mm of space. The use of our motor starter therefore makes it possible to achieve space savings of up to 75%, compared to conventional starter combinations.
Moreover, the integration of four functions – forward rotation, reverse rotation, motor overload protection and Emergency Stop – in just one device negates the need for additional wiring. This reduces the installation time by up to 75%, compared to conventional device combinations.
The third main distinguishing feature is the hybrid switching technology. This makes it possible for the “MOTUS ContactronControl” to perform 30 million electrical switching operations. Users can therefore reckon on a service life that is ten times longer than that of comparable motor starters. As a rule, these achieve only about 3 million electrical switching operations. Furthermore, UL certification also means these devices can be used worldwide, including in the North American market, for example.
The motor starter is just 22.5mm wide and can be mounted with the non-touchable “CrossLink” adapter, both on a 60mm Compact (left) or Classic (centre) busbar system as well as on a top-hat rail (right)
Can you explain the hybrid switching technology in more detail?
H. Lenker: The hybrid switching technology combines the benefits of relay technology as well as wear-free semiconductor switches, thereby eliminating the disadvantages of both elements. The integrated semiconductors provide wear-free switching during activation and deactivation. The mechanical contacts are operated either without power or at very low voltage. This keeps the wear on these contacts extremely low and allows the size of the relay to be reduced to a minimum.
The continuous current is provided by the mechanical contacts, which are arranged in parallel to avoid any problems with the high power dissipation of the semiconductor switches. As this occurs only very briefly, the large heat sinks that are normally required can be omitted.
The up to 9.0A power range of the motor starter is not exactly typical for a component on the busbar system. How does that fit?
M. Engelhardt: Many systems, in which the large number of loads necessitates a busbar system, also have several small drives. When these systems are mounted in a way that saves space and is short circuit-proof, they can easily be placed on the busbar system. That saves a lot of time wiring the system.
For larger drives, our “EQUES” adapter technology up to 630A is available. The small drives up to 4kW can be safely operated with the “MOTUS ContactronControl”. The benefits of the busbar system can be specifically used by combining these large and small drives. Accordingly, the motor starter offers more than just advantages. Reactions from users show that combination of large and small drives on the busbar system delivers even greater benefits.
“The hybrid switching technology combines the benefits of relay technology as well as wear-free semiconductor switches, thereby eliminating the disadvantages of both elements.”
The motor starter can be installed not only on busbar systems, but also on a top-hat rail. Aren’t you moving away from your “CrossLink” technology with this?
M. Engelhardt: Quite the opposite. Depending on which equipment version the customer chooses, the respective “CrossLink” adapter for the 60mm Compact system, the 60mm Classic system or for the DIN support rail is already a part of the “MOTUS ContactronControl” and is supplied with it. All three adapters have the same electrical and mechanical contacting system.
When an electronics module is removed, the adapter’s contacts remain covered to prevent them from being touched. Removal from the adapter and removal of the motor plug make it easy to create visible separation sections for maintenance purposes. It is these advantages, the “CrossLink” technology applied here, which contribute to the simplification of installation, servicing and maintenance.
What future developments can we expect to see with the “MOTUS ContactronControl”?
H. Lenker: Together with Phoenix Contact Electronics and Eaton, Wöhner announced a co-operation in the area of bus technology for use in control cabinets at the Hannover Messe 2012 under the name “Partnership of Experts”. We will use this collaboration to explore new paths in the further development of our busbar system.
One of the next steps will be to connect the motor starter to “SmartWireDT” from Eaton. This will also simplify the control wiring. Interaction with the components available from Eaton will provide a much clear layout for future machine control units.
A connection to “SmartWireDT” is also anticipated for other already available Wöhner products. The aim is to obtain important information from the devices. This will serve to use and monitor existing systems with greater energy efficiency and to further increase reliability through early intervention in the process. And we are also developing further electronic device components for use on “CrossLink” adapters.
Rational Power Distribution
In addition to rapid and secure mounting without the need for drilling, as well as the clearly recognisable allocation of load feeders, the advantages of this busbar system technology lie in particular in the mechanical attachment and simultaneous electrical connection of the components on the busbar system. Busbar terminals and high levels of wiring effort are a thing of the past. Accordingly, the distribution of electrical energy in the low-voltage range is virtually inconceivable today without busbar systems. The favourable dimensions of the 60mm systems have resulted in their widespread use. They are noted for a busbar centre spacing of 60mm between the outer conductors. In the 60mm Classic system from Wöhner, various distribution options, such as a bus-mounting fuse base, switch disconnectors or adapters for motor overload switches, can be implemented in a single system with an installed height of only 200mm.
Wöhner has fuse holders and switchgear in its product range which can be used for the holding of globally used fuses according to IEC and UL (for example, NH, 10x38 or Class CC/Class J). Wöhner has offered the “CrossLink Technology” in the 60mm Classic system since 2008. It offers the user benefits regarding safety during installation and servicing, can be used internationally according to IEC and UL, and also offers planning benefits through the uniform system layout based on the uniform adapter platform. The large range of busbars available even enables distributions of up to 2500A as required, through the use of triple T-profile busbars.
The versatile 60mm Compact system is available for even greater space savings. The space reduction of up to 20% compared to the 60mm Classic system above all results from the smaller installed height of just 160mm instead of 200mm. The uniform busbar centre spacing of 60mm and the same spacing to the mounting platform enables the components from the Compact system to be combined with those from the existing Classic system and vice versa in some instances. In addition to the three-pole version, the 60mm Compact system is also available in a special version – the four and five-pole variant.
Download the Motus® ContractronControl brochure here