Resistors are designed to convert electrical energy into heat, which makes heating of the exhaust air and adjacent housing components unavoidable. Consequently, temperature management is of particular importance for braking resistors. In many cases, these products are used in very confined environments. Products of different designs or multiple braking resistors inevitably influence each other in such situations. A first step is therefore to check the thermal conductivity of the surface on which the braking resistor is mounted. Poor thermal conductivity leads to a higher operating temperature of the resistor. Direct mounting on a heat sink or cooling surface can provide a remedy, significantly increasing the resistor’s continuous power or reducing its surface temperature. Depending on the type and size of the cooling surface or heat sink, the power can be increased by a factor of 1.5 to 4. For maximum safety, it is possible to monitor the resistor’s temperature with a thermal switch. If a nominal temperature is exceeded, the thermal switch opens and activates a signal contact. The thermal switch is equipped with two ready-to-connect wires for this purpose.
If installation conditions are not optimal due to compact structures or protective devices against environmental influences, preventing adequate air supply and exhaust or sufficient heat dissipation via cooling surfaces, REO liquid-cooled systems can be used.
