Hitachi WJ200 Series User Manual

6−20
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.
T/L3
S/L2
R/L1
T/L3
S/L2
R/L1
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 components above in an insulated housing before using them.

Hitachi WJ200 Series Specifications

General

Series	WJ200
Output Frequency	0.1 to 400 Hz
Control Method	V/f Control, Sensorless Vector Control
Overload Capacity	150% for 60 seconds
Enclosure	IP20
Communication	RS-485 (Modbus RTU)
Input Voltage	200-240V AC, 380-480V AC
Ambient Temperature	-10 to +50°C
Storage Temperature	-20 to +60°C
Humidity	5 to 95% RH (non-condensing)
Cooling Method	Fan cooled
Braking Unit	Built-in
Protection Functions	Overcurrent, Overvoltage, Undervoltage, Overheat, Ground Fault
Analog Inputs	2
Analog Outputs	1