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The energy stored from the motor and the inertia load must be consumed, and if the frequency converter is ramping down quickly (which still provides a frequency to the motor), the motor will act as a generator and power the frequency converter.
See the corresponding parameter list for further explanation. Some features may not be available on all drive types; for example, MM410, 420 and 430 do not have a built-in brake unit.
It is forbidden to use the variable speed drive as an emergency stop (EN602049.2.5.4).
1.OFF1: This is the normal and default parking method. When the stop command is issued, the output frequency of the inverter is reduced to zero at the falling ramp rate set by P1121. r If the motor and load have high inertia and the system losses are low, the inertial energy will return to the inverter and the internal DC voltage will rise. The frequency converter then automatically ramps up the ramp time via a voltage controller (P1240-3) to limit the voltage rise. In extreme cases, an overvoltage trip (F0002) will be generated to shut down the frequency converter to prevent excessive voltages from being generated in the DC. At this point, to maintain a controlled ramp rate, the ramp rate P1121 should be extended, or other braking possibilities (see below).

2.OFF2: With OFF2, the inverter directly stops its output, and the motor and load will coast to a stop. If an external mechanical brake is used to prevent the drive from blocking the brake during the ramp down time, then OFF2 should be used. OFF2 is usually controlled by a digital input with a reverse sensor, ie active low and fail safe. Note that if you wish to disconnect the motor (for example, a contactor for safety reasons), an OFF2 should be used before opening the contactor to prevent alarms and faults.

3.OFF3: This provides a faster OFF1 on older drives. In the MM4, only one alternative ramp down time is provided, set by P1135. OFF3 is usually also active low.

4. DC Brake: If a DC current is applied to the motor, a brake torque will be generated. If the motor is stopped, a corresponding hold torque will be generated, which in some cases can effectively replace the mechanical brake. DC access is established via P1230-4 and different timing and frequency options are available. For a further explanation of these parameters, see the parameter list and FAQ7734180.

When DC braking is used, the motor and load inertia are consumed in the motor, and because the DC current is also fed back to the motor, frequent and prolonged use can cause the motor to overheat.
DC braking does not control the motor speed, so the motor's stopping time depends on the load, loss, inertia, etc., and will vary.
The braking torque generated by DC braking is difficult to calculate.

5. Composite brake P1236: The operation of the composite brake is very similar to that of OFF1, but if there is too much energy to return to the inverter, a DC component is added to the output of the inverter.
That is, when the motor frequency is still controlled by the falling ramp, the normal ramp-down frequency is mixed with a DC current, and there is a DC braking effect.
Therefore, the energy is partially consumed on the motor and the speed is controlled. When the frequency converter is operated under sensorless vector control (P1300=20-23), the composite brake does not work. The figure below shows how the composite brake combines the OFF1 brake with the DC brake.

6. Kinetic (or resistance) braking: When OFF1 is used and excess energy is returned to the frequency converter, energy can be dissipated on a braking resistor controlled by a brake transistor or IGBT (circuit breaker). On MM440 units with a maximum frame size F, the brake unit is built into the frequency converter and, if a suitable external resistor is connected, the brake transistor will switch the resistance on the DC bus in a controlled manner to reduce DC Voltage.
The correct choice of resistor is very important to protect the brake transistor, see FAQ 7800906. For example, each form has a minimum allowable size resistance to prevent damage to the brake transistor.
When the brake function is activated by P1237, the braking cycle of the brake transistor can be limited to limit the total dissipation in the resistor for protection purposes. The standard resistor (ie, supplied by the MM4 option) has a braking cycle of 5%, so this setting must be used with these resistors. For applications requiring a braking cycle of more than 5%, the resistor must be obtained from other suppliers according to the guidelines in FAQ 7800906. Some braking resistors also have thermal switches for protection purposes, and the thermal switches can be connected to an alarm or trip.
When using kinetic energy braking, it is recommended to disable the Vdcmax controller by setting P1240=0.

Kinetic Brake Cycle Calculation For a 5% brake cycle, the drive recognizes that the resistor can withstand 12 seconds of full power and then requires 228 seconds of cooling. Obviously, if the time braking time is less than 12 seconds. n or the braking power is less than 100% (which is usually the case), then the 2nd or 3rd braking takes place within 240 seconds. The frequency converter therefore calculates the i2t of the resistor.
For a higher percentage of braking cycles (P1237 = 2, etc.), a multiple increase is allowed. For example, when a frequency converter is braked for 5 seconds at 50% power per minute, it is difficult to accurately calculate what will happen. In this case, it is recommended to install a larger resistance than the theoretical recommendation, and accordingly select a higher braking cycle at P1237.

Example: 7.5kW inverter, braking 5 times in 60 seconds at 50% power, 2 seconds each time. 10 seconds in 60 seconds is equivalent to 40 seconds in 240 seconds; half power is 20/240 = 8%. (624W) Use a 750W resistor and set P1237 = 2 (10%).
See FAQ7800906 for further examples.

Kinetic Brake Alarm and Overload Once the frequency converter has calculated that the energy absorbed by the resistor has reached the amount allowed for the brake cycle calculation, the frequency converter will limit the short-term braking cycle to the setting in P1237. For example, after 12 seconds of 100% loading, P1237 is set to 1 (5% braking cycle), and the power applied to the resistor will be reduced to 5% by the braking cycle limit. If the load starts only from 50%, this will happen after 24 seconds. Alarm A0535 will indicate a 95% load in 10 seconds (or 42% in 20 seconds); that is, just before the brake cycle is forced to decrease.
Under continuous high-load braking conditions, if P1237 is set to a low braking cycle setting, there is a risk of alarms and severe damage to braking capability. If the kinetic energy brake is continued, the inverter may trip and the braking capacity is lost. In this case, it is important to install a resistor of the correct size or, if necessary, ensure that the alarm signal operates a safe brake. Alternatively, a voltage threshold measurement (set the above normal operating point for the brake relay but below the trip level) can be used to operate a relay (P2172, P731 = 53.7/8).

Kinetic braking can be very effective when stopping high inertia loads, but please note that the braking power is limited to 100% of the inverter power (an electrically operated inverter has a short-term overload capability).
7. Mechanical brake control: The frequency converter includes a feature that simplifies the control of the external mechanical brake. Parameter P1215-7 allows the built-in relay to be set to control an external brake brake, allowing the motor to be controlled to brake and release. The brake brake is operated together with OFF1.