Installation and Connection
3-16
3
Power
supply
Thermostat
Braking
resistor
Thermal
relay
Control power
supply
Contactor
CFW-11
BR
DC+
Figure 3.12
- Braking resistor connection
3.2.3.2.2 Installation of the Braking Resistor
Install the braking resistor between the power terminals DC+ and BR.
Use twisted cable for the connection. Separate these cables from the signal and control cables. Size the cables
according to the application, respecting the maximum and effective currents.
If the braking resistor is installed inside the inverter cabinet, consider its additional dissipated energy when sizing
the cabinet ventilation.
Set parameter P0154 with the resistor value in ohms and parameter P0155 with the maximum resistor power
in kW.
DANGER!
The inverter has an adjustable thermal protection for the braking resistor. The braking resistor and
the braking transistor may damage if parameters P0153, P0154, and P0155 are not properly set or
if the input voltage surpasses the maximum permitted value.
The thermal protection offered by the inverter, when properly set, allows the protection of the resistor in case of
overload; however, this protection is not guaranteed in case of braking circuitry failure. In order to avoid any
damage to the resistor or risk of fire, install a thermal relay in series with the resistor and/or a thermostat in contact
with the resistor body to disconnect the input power supply of the inverter, as presented in figure 3.12.
R
S
T
NOTE!
DC current flows through the thermal relay bimetal strip during braking.
