Onset H21 Specifications

WattNode® Pulse Output kWh Transducer Connection Instructions

For use with HOBO® H21, H22, U30, UX90, and UX120 series data loggers, and HOBO data nodes

Applies to these WattNode Pulse Output kWh Transducers:

Onset Part No. Configuration / VAC Output Maximum Pulse Output WattNode Part No.

T-WNB-3Y-208 Single-phase 120 or

Wye 208-240

T-WNB-3Y-208-P Single-phase 120 or

Wye 208-240

T-WNB-3D-240 Delta 208-240 Pulses representing kWh 4 Hz WNB-3D-240-P

T-WNB-3D-480 Delta (or Wye) 480 Pulses representing kWh 4 Hz WNB-3D-480-P

Pulses representing kWh 4 Hz WNB-3Y-208-P

Pulses representing kWh 4 Hz WNB-3Y-208-P

option P3

DANGER!—HIGH VOLTAGE HAZARD

Installing transducers in an energized electrical enclosure or on any energized conductor can result in severe injury or death.
These transducers are for installation by qualified personnel only. To avoid electrical shock, do not perform any installation or
servicing of these transducers unless you are qualified to do so. Disconnect and lock-out all power sources during installation
and servicing. Please read transducer user manuals for instructions and use.

This document provides instructions on connecting the WattNode Pulse Output
kWh Transducers listed above to HOBO H21, H22, U30, UX90, and UX120
series data loggers and to ZW series data nodes. Note: For information on
connecting the kWh transducer to the power source and other transducer
details, refer to the WattNode documentation provided by Continental Control
Systems.

Required

• Selected WattNode Pulse Output kWh Transducer

• Appropriately rated Current Transducer(s)

• Smart Sensor-compatible HOBO data logger (H21, H22, or U30 series) with:

o Pulse Input Adapter(s), Onset Part No: S-UCC-M00x*

®

o HOBOware

Pro Software, version 2.2 or higher (2.4 or higher for U30)

• 22 AWG twisted pair wire (customer supplied) for UX120 series with HOBO Pro Software, version 3.2.0 or higher

• Pulse input-compatible HOBO data node (ZW series) and HOBO data logger (UX90 series) with:

o Onset Part No: CABLE-2.5-STEREO*
o HOBOware Pro Software, version 3.0 or higher for ZW series and version 3.3 or higher for UX90 series

* For monitoring power demand as well as generated power, a second S-UCC-M00x pulse input adapter (for H21, H22, or

U30 series) or CABLE-2.5-STEREO (for pulse input-compatible ZW series) is required (at output terminal P2).

WattNode Pulse Output kWh Transducer

(Onset Part No. T-WNB-3Y-208-P shown)

WattNode Pulse Output kWh Transducer Features

• The WattNode transducer includes three LEDs—one per phase—for diagnostics and indication of power direction, low

power factor, and correctly installed CTs.

• The WattNode transducer provides bidirectional power measurements (positive and negative power). It can be used for

conventional power and energy measurement as well as for net metering and PV applications. For monitoring power
demand as well as generated power, a second S-UCC-M00x pulse input adapter (for H21, H22, or U30 series) or
CABLE-2.5-STEREO (for pulse input-compatible ZW series) is required (at output terminal P2).

© 2005–2012 Onset Computer Corporation. All rights reserved. Onset, HOBO, and HOBOware are registered trademarks of Onset
Computer Corporation. Other products and brand names may be trademarks or registered trademarks of their respective owners.

Manual Part No: MAN-WATTNODE
Doc No: 10332-K

WattNode Pulse Output kWh Transducer Connection Instructions

• The T-WNB-3Y-208-P can measure two or three separate branch circuits simultaneously. Note that an S-UCC-M00x

pulse input adapter (for H21, H22, or U30 series) or a CABLE-2.5-STEREO (for pulse input-compatible ZW series) is
required for each circuit monitored.

Note: Refer to the WattNode WNB Series Installation and Operation Manual for details of these features.

Configuring the System

To configure the system, refer to the applicable connection diagram that corresponds to your electrical power configuration.
Also refer to the WattNode manual for additional configurations.

Connect to

Smart Sensor port

Customer-supplied

22 AWG twisted pair

HOBO H21, H22, or U30 Series Data Logger

HOBO UX120 Series Data Logger

Connect (+) terminal from

UX120 terminal block to P1

Connect ground ( ) terminal from

UX120 terminal block to COM

(H22-001 shown)

S-UCC-M00x

Pulse Input Adapter

P3
P2
P1

Output

COM

P3
P2

White

P1

Output

COM

Black

HOBO ZW Series Wireless Data Node

Connect to

pulse port

CABLE-2.5-STEREO

HOBO UX90-001/M Data Logger

CABLE-2.5-STEREO

Red wire
not used

White

Black

Red wire
not used

P3
P2
P1

COM

White

Black

Output

Figure 1: Connecting HOBO Data Logger or Data Node to WattNode

Electrical Service Types

Below is a list of service types, with connections and recommended WattNode models. Note: the WattNode ground
connection improves measurement accuracy, but is not required for safety.

P3
P2
P1

COM

Output

Model Type

Phase to

Neutral

WNB-3Y-208-P Wye 120 VAC

Phase to

Phase

208–240

VAC

Electrical

Service Types*

1 Phase 2 Wire 120V with neutral
1 Phase 3 Wire 120V/240V with neutral
3 Phase 4 Wire Wye 120V/208V with neutral

1 Phase 2 Wire 208V (No neutral)
1 Phase 2 Wire 240V (No neutral)

WNB-3D-240-P

Delta

or Wye

120–140

VAC

208–240

VAC

1 Phase 3 Wire 120V/240V with neutral
3 Phase 3 Wire Delta 208V (No neutral)
3 Phase 4 Wire Wye 120V/208V with neutral
3 Phase 4 Wire Delta 120/208/240V with neutral

3 Phase 3 Wire Delta 480V (No neutral)
3 Phase 4 Wire Wye 277V/480V with neutral
3 Phase 4 Wire Delta 240/415/480V with neutral

WNB-3D-480-P

Delta

or Wye

277 VAC 480 VAC

*The wire count does NOT include ground. It only includes neutral (if present) and phase wires.

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WattNode Pulse Output kWh Transducer Connection Instructions

Single-Phase Two-Wire with Neutral

This configuration is most often seen in homes and offices. The two wires are neutral and line. For these models, the
WattNode is powered from the N and ØA terminals.

Figure 2: Single-Phase Two-Wire Connection

Recommended WattNode Model

The following table shows the WattNode model that should be used, depending on the line to neutral voltage.

Line to Neutral Voltage WattNode Model

120 VAC WNB-3Y-208-P

Single-Phase Three-Wire

This configuration is seen in North American residential and commercial service with 240 VAC for large appliances. The
three wires are neutral and two line voltage wires with AC waveforms 180° out of phase; this results in 120 VAC between
either line wire (phase) and neutral, and 240 VAC (or sometimes 208 VAC) between the two line wires (phases).

Figure 3: Single-Phase Three-Wire Connection

Recommended WattNode Models

The following table shows the WattNode models that can be used. If neutral may or may not be present, you should use the
WNB-3D-240-P (see Single-Phase Two-Wire without Neutral below). If neutral is present, it must be connected for accurate

Page 3 of 7