Yokogawa CW240
Clamp on Power Quality Meter

• Easy-to-read LCD screen display
• Up to 4 loads can be measured
• Connection checking function
• Portable
• Built-in 1MB Internal Memory; Can be expanded up to 512MB by use of external Memory cards
• Multi-Lingual Support
• Zoom Function
• Backup Power supply attachments available

Yokogawa CW240 Shown
 

The CW240 supports four single-phase two-wire systems, two single-phase three-wire systems and even SCOTT connections. The CW240 supports currents ranging from 200.0 mA to 3000 A and voltages up to 1000 V. Electric power (instantaneous values, electric energy, and demand), harmonics, voltage fluctuations (dip, swell, and instantaneous power failure) and waveform scan all be measured simultaneously.

Measurement of Instantaneous Values:
The CW-240 can be used to carry out investigation regarding renewal of electric equipment such as transformers in building, check load factors and demand factors, and to check current/voltage fluctuation at motor start-up.

• Measurement elements: Voltage/current/electric power (active, reactive, apparent)/power factor/phase angle of each phase, average/minimum/maximum values of each measurement element.
• Data collection time: 1/2/5/10/15/30 seconds, 1/2/5/10/15/30/60 minutes One cycle (waveform), 100/200/500 ms (short time interval)

Power Quantity Measurement:
The CW-240 can measure and display the power quantity consumed up to the specified time (from the start of integration until the end).

• Measurement elements: Active power quantity, regenerative power quantity, reactive power quantity (leading/lagging)


• Data collection time: 1/2/5/10/15/30 seconds, 1/2/5/10/15/30/60 minutes

Demand Measurement:

• Measurement elements:
  • Maximum power demand required since the start of logging measurement and the time it occurs
  
  • Active power, reactive power (lag), power factor
  • Active power quantity (consumption, regeneration), reactive power quantity (lagging/leading)
    
• Demand
  
  • Demand time limit: Length of time set to obtain the average power (normally 30 minutes)
  • Demand power: Average power during the demand time limit

• Harmonics for Analysis: 1st to 50th
• Display Data: List, Bar graph (linear/log), vector (inflow/outflow judgment)
• Measurement Elements: Level, Content, phase angle (voltage/current/electric power of each harmonic), aggregate value (voltage, current, electric power, power factor), aggregate harmonic distortion factors (THD-F or THD-R) of voltage/current
• THD-F: Distortion factor for the fundamental wave, THD-R: Distortion factor for all rms values voltage/current
  
• Data collection time: 1/2/5/10/15/30/60 minutes

Waveform Measurement:

• Measurement elements: Voltage of each phase, current of each phase
  Voltage and current of each phase


• Data saving format: Binary (can be converted to CSV format using a standard application program)
   

Voltage Fluctuation Measurement:
The CW240 detects dates/times of when fluctuations occur, fluctuation type, channels where they occur, rms values, and periods between start and end. The voltage threshold is set, and fluctuations exceeding the threshold are detected.

• Measurement element: Voltage dip (voltage drop), voltage swell (voltage rise), instantaneous power failure
• Data saving: Detected based on the voltage rms value of one waveform. Up to 100 data sets can be saved.

• Writing Check Function
  Prior to start of measurement, the CW-240 checks whether wiring is correct. Wiring errors, reverse connection of current clamps, and phases to be checked can be displayed in a vector diagram.



• Setting Check Function:
  Settings made for data saving can be checked in the screen. This prevents data acquisition errors that may occur due to mistakes in voltage range setting, current clamp selection or data save item selection.