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WattNode KWH Transducer

Brand: Onset HOBO
Product Code: T-WNB-3Y-400-P
WattNode KWH Transducer
Ex VAT £268.46 Inc VAT £322.15

Availability: In stock

SKU: T-WNB-3Y-400-P

Product Description


The Advanced Pulse WattNode is a true RMS AC watt-hour transducer with pulse output (solid state relay closure) proportional to kWh consumed. The WattNode provides accurate measurement at low cost to meet your needs for sub-metering, net-metering, energy management, and performance contracting applications. The complete Pulse Output family measures 1, 2, or 3 phases in 2, 3, or 4 wire configurations. With voltage ratings from 120 to 600 Vac and current transformer (CT) ratings from 5 to 6000 amps, there is a WattNode combination to meet your AC power measurement requirements.



VAC Phase

VAC Phase



to Neutral

to Phase

Service Types





1 Phase 2 Wire 230V with neutral


3 Phase 4 Wire 230V/400V

Diagnostic LEDs

  • The diagnostic LEDs provide a per-phase indication of power (green flashing) and negative power (red flashing) to help troubleshoot connection problems, like swapped CTs, or excessive line voltage. See the manual for a full description.

Advanced Output Capabilities are available as factory options:

  • Standard output provides pulses on one terminal for positive energy and on another terminal for negative energy. This is useful with solar panels, where energy taken from the grid and energy fed to the grid can be metered separately with one meter (net metering).

  • For more information on available options click the Options tab.

Key Features and Benefits

  • Pulse output—Compatible with energy management systems and data loggers.

  • 0.5% nominal accuracy (see manual for details)

  • Small size—Can be installed in existing service panels or junction boxes.

  • Bidirectional metering—Net metering for PV (photovoltaic) solar and wind power generation with only one meter.

  • Advanced metering design—Enables metering of variable frequency drives.

  • Safe CTs—Integral burden resistor limits the output to low voltage.

  • Line powered—No external supply required.

  • Detachable terminal blocks—Easy to install and remove.

  • UL, cUL Listed—Designed and tested for safety and use throughout North America.

  • CE Mark—Can be installed throughout the EU.

  • The optional LCD display module remotely displays energy in Wh, kWh, or MWh; or power in W or kW

  • Small form factor for easy installation inside most electrical panels, see a sample installation diagram

  • Assembled in USA, qualified under the Buy American provision in the American Recovery and Reinvestment Act of 2009 (ARRA).

  • Five year warranty


Safety Note

Warning: Hazardous Voltages - Only qualified personnel or licensed electricians should install the WattNode meter and current transformers.



Call +44 (0)1243 558270, click on the webchat box below, or fill out our contact form.

Availability: In stock

Additional Information

Additional Information

Typical Applications Energy, Environmental (Indoor)
Measurements kWh
Compatible With U30, H21, H22, ZW, UX120