Inverter Output Voltage Measurement Techniques

L100 Inverter

6–13

Inverter Output Voltage Measurement Techniques

Taking voltage measurements around drives equipment requires the right equipment and a safe approach. You are working with high voltages and high-frequency switching waveforms that are not pure sinusoids. Digital voltmeters will not usually produce reliable readings for these waveforms. And, it is usually risky to connect high voltage signals to oscilloscopes. The inverter output semiconductors have some leakage, and no-load measurements produce misleading results. So, we highly recommend using the following circuits to measure voltage for performing the equipment inspections.

Troubleshooting and Maintenance

Voltage measurement with load

L1(L)		U/T1
L2	Inverter	V/T2
L3(N)		W/T3
		220 kΩ
		2W
		+	–

V class	Diode bridge	Voltmeter
200V class	600V 0.01A min.	300V range
400V class	1000V 0.1 A min.	600V range

Voltage measurement without load

L1(L)			U/T1
L2	Inverter		V/T2
L3(N)			W/T3
Additional resistor
	5 kΩ	30W
		220 kΩ
			2W
			+	–

V class	Diode bridge	Voltmeter
200V class	600V 0.01A min.	300V range
400V class	1000V 0.1 A min.	600V range

HIGH VOLTAGE: Be careful not to touch wiring or connector terminals when working with the inverters and taking measurements. Be sure to place the measurement circuitry above in an insulated housing before using them.

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 Inverter Output Voltage Measurement Techniques, Additional resistor

Models: L100

L100 Inverter

Inverter Output Voltage Measurement Techniques

Voltage measurement with load

L3(N)

Voltage measurement without load

Additional resistor

L100 specifications