Yokogawa CW121-D-2 Clamp On Power Meter, Power Cord: UL/CSA Standard, Interface RS485.

Low-cost tools to support your energy conservation efforts
As energy conservation becomes increasingly important, we are pleased to present low-cost clamp-on power meters designed to meet user needs for simple tools capable of measuring power values and instantaneous values.

Useful features for energy conservation and power measurement

• Periodically save data as often as once a second

Data can be saved as low as 1-second interval. This capability allows the CW120 Series to respond quickly to load fluctuations and measure transient responses in equipment.

• Check equipment operating conditions

The CW121 Series has an instantaneous value filing function (enabling multiple data records to be saved in a single file when multiple measurements are taken) which is useful for determining equipment operating conditions.

• Wiring error check function

This function helps ensure that measurement operations are correct.

• Simultaneous measurement of multiple facilities

Multiple CW120 Series units can start and stop integration simultaneously through externally controlled I/O.

• Works even with small electric energy values

Easily change the decimal position (the number of digits following the decimal point) and display unit (Wh, kWh, MWh, GWh) on the electric energy display.

Details for Models CW120/CW121
 

Items		CW120/CW121
Measurement Mode	Input system	Single-phase 2-wire to 3-phase 4-wire
	Instant mode	(Up to 3 phase 3 wire for CW120)
	Electric Energy mode	Available
Display	Screen	Segmented LCD with backlight
Communication	Interface	RS232 or RS485
	Protocol	MODBUS, PC-link, Power-Monitor, Proprietary
	Monitoring by AP240E	Available
Power supply		100 to 240V AC, Supply the power from input.
Size (WxHxD)		117x161x51mm
Weight		600g

Load measurements on multiple systems

In addition to support for a variety of connection types, The CW120 Series can simultaneously measure the loads* (facilities, equipment) on multiple systems sharing a common power supply. CW120 (three-phase 3-wire model): 1ø2Wx2 CW121 (three-phase 4-wire model): 1ø2Wx2, x3

Compact design

• The CW120 Series is compact in size (117x161x51mm (WxHxD)), making it ideal for installation in cubicles and inside distribution panels. Installation is even easier with the magnetic case (93023).
• Although the CW120 Series is small, it has a large backlit LCD.
• A new addition to the clamp lineup is a small-diameter current clamp (model 96033, capable of measurements in the range of 5–50 A) for measurements in tight spots and locations where many wires are jumbled together.

Measurements

• The CW120 Series can be used for voltage measurements up to 495 V.
• A variety of connection types are supported, from single-phase 2-wire to three-phase 4-wire (CW120: three-phase 3-wire model; CW121: three-phase 4-wire model).
• Continuous measurement integration (accurate measurements can be obtained even if there are large load fluctuations)
• Plus/minus signs are shown for reactive power and power factor.
• The data saving interval can be set in the range of one second to one hour.

Parameters setting tool (name: Toolbox)

The setting software allows you to set CW120 Series measurement conditions through a PC and save measurement data on a PC when the unit is connected to the PC through RS-232 or RS-485 port.

• Measurement conditions setting function

This function makes it easy to set basic functions needed for measurement, such as start/stop time and date, wiring method, clamp type, voltage, and current range etc. 

• File transfer function 

The data file stored in CF pack can be transfered to PC. Microsoft Excel can read transferred data file. * Toolbox is included as a standard feature (on two floppy disks).
 

Data management and communication

1. You can connect CW120 to a PC through dedicated RS-232 cable.
2. A printer (sold separately) can be connected through RS-232 cable to print measurement data.
3. If you have a media reader connected to your PC or card slot in notebook PC, measurement data and settings can be uploaded directly to a PC from CF* pack.

Network Communication

CW120 In addition to proprietary communication also supports, MODBUS, PC-link and Power Monitor protocols. PC-link is a protocol for Yokogawa's Temperature controllers and PLCs. Power Monitor protocol is a protocol for Yokogawa's Power Monitors. (PR201)


* DAQLOGGER is Yokogawa’s communication software for Windows

Remote monitoring

The RS-485 allows multiple use to be connected for remote monitoring.

* RS-485/RS-232 converter is required to connect the CW120/CW121-m-2 (RS-485 communication spec) to the RS-232 port on your PC.

Recommended brand and model: Yokogawa’s RS-232/RS-485 Converter Model  ML2.