So that we can also provide resistance tomorrow

Braking resistors from GINO AG are particularly low-maintenance and wear-free, which is the only way we can maintain our leading market position and withstand your scrutiny - and have been doing so for over 40 years. We are not resting on our laurels, but are driving the development of a modern braking resistor. High-quality materials and production in Germany in accordance with the latest quality and environmental standards are our basis. As individual as you are: our brake resistors always include a tailor-made solution - suitable for your industry, climate and performance classes.

Optimized brake resistors - so as not to slow down the future

Especially today, when the focus is on energy efficiency, an innovative braking resistor is the way forward. Modern motors are particularly energy-efficient, which also reduces the braking power required. For this reason, braking resistors must not only be smaller, but also particularly solution-oriented. Accordingly, it is no longer sufficient to classify braking resistors as wirewound, steel or cast iron resistors. This is why GINO AG offers an individual braking resistor for each resistor system and application. In close cooperation with our customers, we adapt our resistor solutions individually to the existing overall system.

What is a braking resistor?

A braking resistor converts kinetic energy into thermal energy (heat) during braking, which slows down a motor. This physical phenomenon, which will not change despite modernization, involves the resistance value, the dimensions and the machines. Whether braking completely or merely reducing speed, the kinetic energy of a system must be reduced or completely dissipated. To achieve this, electrical energy is fed to the braking resistor, which has a certain resistance value, in the intermediate circuit of the frequency inverter. This electrical energy is in turn converted into heat by flowing through the braking resistor. This causes the speed of the moving body to decrease, slowing it down. The dimensions of the braking resistor are designed in such a way that it can efficiently dissipate the heat generated. The machines, such as the motor and the frequency converter, work together to control the braking process and ensure that the kinetic energy of the system is successfully converted into heat.

How does a braking resistor work?

The braking resistor is operated in parallel with the DC link and is clocked by pulse width modulation as soon as the voltage in the DC link exceeds a defined voltage level. The current flowing through the braking resistor heats the resistor material. This heat is released into the atmosphere and dissipated by natural convection.

What tasks do frequency inverters perform with braking resistors?

The speed of a three-phase squirrel-cage motor can be controlled by changing the frequency of the supplied voltage. For this purpose, frequency converters are operated whose output frequency can be controlled independently of the mains frequency. The three-phase current from the mains is first converted into direct current in an intermediate circuit and then into a three-phase current with a variable frequency.

What needs to be considered with frequency converters for braking resistors?

Frequency inverters can be used unchanged for drives that operate in the I. and III. quadrants of the n/M diagram. These are drives whose moment of inertia is considerably smaller than the load torque. However, four-quadrant drives require an additional device to absorb the kinetic energy.

What is slip in electric motors?

In simple terms, slip refers to the deviation in speed between two elements that are in contact with each other. This always happens when a motor is under load, as its armature then lags behind the frequency of the supply voltage. If the frequency inverter reduces its frequency or if the motor is driven by external operating conditions, which happens, for example, during dips or downhill runs, then the rotor frequency is higher than that of the supplying inverter. The rotor sequence is said to be oversynchronized - the motor becomes a generator. The regenerative energy leads to an increase in voltage in the intermediate circuit of the frequency inverter and must be dissipated, for example by means of regenerative braking. However, it should be borne in mind that it is not always possible or economically viable to feed energy back into the grid.

Where are braking resistors used?

For all drives that require increased speed changes or excess power is not consumed by the loads or losses of the driven machine, such as:

Hoists and trolleys
elevator drives
conveyors
Drives on handling equipment

How are braking resistors installed?

Braking resistor for lower power ratings: As a rule, resistors for lower power ratings can be installed together with the other devices in the switchgear. The resistors are available with IP65 for this low power.

Braking resistor for high power ratings: Due to heat generation and the resulting high temperatures, resistors for higher power ratings usually have their own housing and are installed separately. The possible degrees of protection here range from IP00 to IP23.

What braking resistors are available?