Dynamic Braking, HRB1 HRB2 HRB3 | Hitachi L100 guide

L100 Inverter

5–5

Dynamic Braking

The purpose of dynamic braking is to improve the ability of the inverter to stop (deceler- ate) the motor and load. This becomes necessary when an application has some or all of the following factors:

•High load inertia compared to the available motor torque

•The application requires frequent or sudden changes in speed

•System losses are not great enough to slow the motor as needed

When the inverter slows its output frequency to decelerate the load, the motor can temporarily become a generator. This occurs when the motor rotation develops a voltage higher than the inverter internal (DC) bus voltage. This condition can cause the inverter to have an over-voltage fault and enter the Trip Mode. In many applications, the over- voltage condition serves as a warning signal that we have exceeded the deceleration capabilities of the system. The L100 inverter can connect to an external braking unit, which accepts the excess energy from the motor during deceleration to its internal resis- tor(s). The power resistor serves as a generator load, developing heat to stop the motor just as brakes on an automobile develop heat during braking. You can also add an external resistor to the braking unit for additional braking torque.

A switching circuit and power resistor are the main components of the dynamic braking unit, which includes a fuse and thermally activated alarm relay for safety. However, be careful to avoid overheating its resistor. The fuse and thermal relay are safeguards for extreme conditions, but the inverter can maintain braking usage in a safe zone. The following table specifies the braking options for 200V class L100 inverters and the braking torque for each option. Use BRD–E2 braking unit for 200V class inverters.

L100 Inverter 200V Models					BRD–E2 Braking Unit

		Braking torque	Using built-in			External resistor added
			Using built-in
			resistor only
Model Number	HP	without	resistor only		HRB1		HRB2		HRB3
Model Number	HP	without			HRB1		HRB2		HRB3
		braking unit
		braking unit	A	B	A	B	A	B	A	B
			A	B	A	B	A	B	A	B


002NFE/NFU	1/4	50%	150%	120%	Over-range		Over-range		Over-range

004/005NFE/NFU	1/2	50%	150%	120%	Over-range		Over-range		Over-range

007NFE/NFU	1	50%	100%	80%	150%	120%	Over-range		Over-range

011/015NFE/NFU	2	50%	60%	60%	100%	80%	150%	120%	Over-range

022NFE/NFU	3	20%	50%	50%	100%	80%	120%	100%	Over-range

037LFU	5	20%	40%	40%	60%	60%	80%	80%	150%	120%

055LFU	7.5	20%	30%	30%	50%	50%	60%	60%	100%	80%

075LFU	10	20%	—	—	40%	40%	60%	60%	80%	80%

Note 1: A = Average braking torque from 60 Hz to 3 Hz.

Note 2: B = Average braking torque from 120 Hz to 3 Hz.

Note 3: BRD maximum duty cycle = 10%, where Tb/Tc ≤ 0.1 sec.

Note 4: BRD maximum continuous On time Tb ≤ 10 sec.

output f

Tb time

L100 specifications

The Hitachi L100 series is a versatile range of variable frequency drives (VFDs) designed to enhance performance in various industrial applications. Known for their reliability and efficiency, these drives are widely used in motors for pumps, fans, compressors, and conveyors.

One of the main features of the Hitachi L100 is its impressive control capabilities. The drive supports both scalar and vector control modes, allowing for precise speed and torque management. This flexibility ensures optimal motor performance across different load conditions. Additionally, the L100 series offers an impressive speed range, which can accommodate a wide variety of applications, from low-speed to high-speed requirements.

The L100 is equipped with built-in functionality for energy saving. By utilizing advanced control algorithms and auto-tuning features, the drive optimizes energy consumption, reducing operational costs and contributing to improved overall system efficiency. The energy-saving mode is particularly beneficial in applications where load conditions frequently change.

Another hallmark of the Hitachi L100 is its robust communication capabilities. The drive supports various communication protocols including Modbus and Ethernet, making it easy to integrate into existing control systems. This connectivity allows for real-time monitoring and diagnostics, which aids in predictive maintenance and minimizes downtime.

In terms of user-friendliness, the L100 series includes a clear, intuitive keypad that simplifies programming and operation. The drive also features a wide range of customizable parameters, enabling users to easily tailor the settings to suit specific application requirements. Additionally, the inclusion of a customizable PID controller allows users to refine process control automatically.

Safety is a priority in the design of the Hitachi L100. The drive comes with various built-in safety features such as overvoltage, overload, and short-circuit protection, ensuring reliable operation in challenging environments. Furthermore, it complies with global safety standards, making it suitable for international applications.

Lastly, the L100's compact design ensures easy installation and minimizes the space required in control cabinets. This is especially advantageous in facilities where space is at a premium. Overall, the Hitachi L100 series represents a combination of advanced technology, user-friendly features, and reliable performance, making it a popular choice for industrial automation solutions.

Hitachi L100 instruction manual Dynamic Braking, HRB1 HRB2 HRB3

Models: L100

L100 Inverter

Dynamic Braking

HRB1

HRB2

HRB3

braking unit

L100 specifications