Description

The BW../BW..-T braking resistors are adapted to the technical characteristics of the inverter. Braking resistors with different continuous and peak braking powers are available.

The braking resistors can be protected against overload and overtemperature by the customer when a thermal overload relay is used. The tripping current is set to the value IF. For further information, refer to chapter Technical data and assignment to an inverter.

A flat-type resistor has internal thermal protection (fuse cannot be replaced) that interrupts the current circuit in the event of overload. The configuration guidelines and the documented assignments of the drive inverter and braking resistor must be adhered to.

Note that with flatpack resistors, the internal thermal protection is only effective at line voltages ≥ 380 V. For line voltages < 380 V, the protection of the braking resistors against overload and overtemperature can only be ensured otherwise, e.g. with a customer-supplied thermal overload relay.

A PTC braking resistor protects itself (reversible) against regenerative overload by changing abruptly to high resistance and no longer consuming any more energy. The inverter then switches off and signals an "overvoltage" fault.

INFORMATION

Use only the following protection devices:
  • Internal temperature switch T
  • External thermal overload relay