Protection of braking resistor against thermal overload

To avoid thermal damage of the braking resistor as well as subsequent damage, the braking resistor has to be thermally monitored.

This can be realized either via a BW...-T braking resistor with an internal temperature switch or via an external thermal overload relay.

If the thermal monitoring device records an overload, the power supply module reacts to this and prevents additional energy from being drawn from the power grid.

The connection to the energy storage unit is disconnected at the same time. The application comes to an idle state. The braking resistor can cool down. The wiring diagram for this situation can be found in chapter Protecting braking resistors against thermal overload.

Connect a power supply module of type MDP90A with a braking resistor to a 24 V switched-mode power supply with a line connection.

Flat-type resistors and PTC resistors are intrinsically safe and therefore do not require additional thermal monitoring.