5 Commissioning | LXM32 |
5.2LXM32: Setting the braking resistor parameters
An insufficiently rated braking resistor can cause overvoltage on the DC bus. Overvoltage on the DC bus causes the power stage to be disabled. The motor is no longer actively decelerated.
WARNING
MOTOR WITHOUT BRAKING EFFECT
•Verify that the braking resistor has a sufficient rating.
•Verify that the parameter settings for the braking resistor are cor- rect.
•Verify that the I2t value for temperature monitoring does not exceed 100% by performing a test run under maximum load con- ditions.
•Verify that the calculations and the test run take into account the fact that the DC bus capacitors can absorb less braking energy at higher mains voltages.
Failure to follow these instructions can result in death, serious injury, or equipment damage.
The temperature of the braking resistor may exceed 250 °C (482 °F) during operation.
WARNING
HOT SURFACES
•Ensure that any contact with a hot braking resistor is avoided.
•Do not allow flammable or
•Verify that the heat dissipation is sufficient by performing a test run under maximum load conditions.
Failure to follow these instructions can result in death, serious injury, or equipment damage.
▶Check the parameter RESint_ext. If you have connected an external braking resistor, you must set the parameter to "external".
▶If you have connected an external braking resistor, (value of the parameter RESint_ext is set to "external"), you must assign the appropriate values to the parameters RESext_P, RESext_R and RESext_ton. Verify that the selected external braking resistor is really connected.
▶Test the function of the braking resistor under realistic, worst case conditions.
If the regenerated power becomes greater than the power that can be absorbed by the braking resistor, an error message is generated and the power stage is disabled.
See the product manual for a description of the parameters.
MNA01M001EN, V1.01, 08.2014
54 | Common DC bus |
