Contactors
NO = Normally Open, NC = Normally Closed. This describes the state of a contactor when the voltage in the system is off. Normally open (NO) is mostly used in electrical systems where, for safety reasons, you want to be sure that the contactor opens when the power is cut in the system in case of a power failure. Normally Closed (NC) is often used when you want to be sure that the contactor closes a circuit in the event of a voltage drop, such as a power failure. to drain the system of energy to earth.
Read more about our DC contactors for both high and low voltage here.
A contactor is defined according to IEV ref 441-14-33 as a mechanical switching device with only one rest position, operated other than by hand, capable of switching on, conducting and breaking currents under normal circuit conditions including operational overload.
In common parlance, this usually refers to an electromechanical contactor where the operation of switching on and off is done by means of an electrically driven coil. Simply put, the contactor is essentially a switch for electrical power in the same way that a relay is a switch for electrical signals or small loads.
With electrification and higher voltages in systems, contactors capable of extinguishing the resulting arc are required to safely interrupt the current, even under load in an emergency. It is therefore important to have the right contactor for the purpose. Factors to consider when choosing a contactor are current, voltage, current direction, inductance, short-circuit current, etc. This is to ensure that the current is actually broken and does not lead to more catastrophic events such as fire or similar, read more about risks here. Please contact us for help in choosing a contactor for your system.
See our range of contactors and contacts here
This question must be broken down into several parameters. The amount of current that can flow through the contactor continuously is determined by the heat dissipation capacity and the maximum continuous current is often referred to as Ith or thermal current. Often a higher current can be run for a shorter time.
When switching off or breaking under load, an arc is always created. The energy in the arc is determined by the current and voltage and the type of load being broken. The arc is ionized gas, s.k. plasma. The energy of the arc is very high and powerfully destructive for the e.g. the contacts. Depending on the design, the contactor can handle the arc in different ways. The aim is always to cool the energy in the arc to create a safe situation and reduce wear and tear. The breaking capacity is always given in amperes at a specific voltage and time constant of the load.
When switching under load, small arcs may form but these disappear as soon as the contact is closed. The capacity for switching is often much greater than for breaking and is given in amperes at a specific voltage and time constant for the load.
When an electromechanical component such as a contactor is exposed to a situation that causes it to fail, it does so safely. A contactor that has arc extinguishing in air will be able to break the current without damaging other components. In gas-filled and contactors with closed arcing chambers, there is a risk of large pressure differences occurring due to. heating, this can lead to explosions with uncontrolled consequences, e.g. current conductors can risk damaging surrounding components.
A contactor is a vital safety component in any electrical system, Schaltbau stands for new patented technology. By far the longest life cycle, resulting in a low price. The patented open arc chamber technology will be larger in volume. Achieving the highest level of safety requires longevity, technical innovation and documented approval.
Contactors
Contactors
Contactors
Contactors
Contactors
Contactors
Contactors
Contactors
An extremely reliable and super compact DC contactor.
The contactors of the CPP series are the smallest Schaltbau switching devices in the power class up to 200 Ampere and suitable for nominal voltages up to 1,500 Volt.
The single-pole contactors are available as NO or NC contactors.
The CPP contactor is used as a precharge contactor for the larger contactors in the Schaltbau catalog, the CP and CT series.
Applications include railway vehicles, but also converters and inverters in the renewable energy sector or, more generally, in industrial environments and DC labs.