AC Power Measurement
for BACnet Networks,
True Power, kWh
Reactive Power,
VARs, Power Factor,
Individual Phase Measurements

 

Model	VAC Phase to Neutral	VAC Phase to Phase	Electrical Service Types	Neutral Required
WNC-3Y-400-BN	230	400	1 Phase 2 Wire 230V with neutral 3 Phase 4 Wire 230V/400V	Yes
WNC-3D-400-BN	See Below	400	3-Phase 3-Wire Delta 400V (No neutral) 3-Phase 4-Wire Wye 230/400V

Delta models, WNB-3D-400-P, work either with or without a neutral connection, but require a line-to-line voltage connection for operating power.

 

WattNode BACnet

The WattNode BACnet (MS/TP) is a kilowatt hour kWh energy and power meter that communicates on a EIA RS-485 network, measures 1, 2, or 3 phases with voltages from 120 to 600 volts Vac and currents from 5 to 6,000 amps in delta (phase to phase) and wye (phase to neutral) configurations.

Diagnostic LEDs

Our diagnostic LEDs provide a per-phase indication of power (green flashing) and negative power (red flashing) to help troubleshoot connection problems, like reversed CTs, or excessive line voltage. The WattNode BACnet meter also has a red/yellow/green communication LED to indicate traffic, configuration problems, bus contention and other conditions. See the manual for full descriptions.

Measurements

• True RMS Power: Watts (Phase A, B, C, and sum of all phases)
• Reactive Power: VARs (Phase A, B, C, and sum of all phases)
• Power Factor: (Phase A, B, C, and average of all phases)
• True RMS Energy: Kilo-Watthours kWh (Phase A, B, C, and sum of all phases)
• Reactive Energy: kVAR-hours (Phase A, B, C)
• AC Line Frequency
• RMS Voltage: (Average and Phase A, B, C; line-to-line and line-to-neutral)
• Computed RMS Current: (Phase A, B, C)
• Demand
• Peak Demand

Features

• Small form factor for easy installation inside most electrical panels, see a sample installation diagram
• Pluggable screw terminals for easy wiring
• 0.5% accuracy nominal (see manual for details)
• True RMS power even with leading or lagging power factor and chopped or distorted waveforms
• Measure variable speed drive pumps and motors
• Uses safe CT’s (current transformers), producing 0.333 Vac at rated current.
• Split core CTs for quick installation
• Solid core CTs are less expensive and prevent tampering
• Bus bar CTs for high current applications (standard and custom sizes)
• UL, cUL Listed, CE Mark – Designed and tested for safety and use throughout North America and the European Union.
• 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.

General Options

Option CT=xxx/yyy/zzz – Pre-assign xxx to CtAmpsA, yyy to CtAmpsB, and zzz to CtAmpsC.
These can be field configured or overridden using the CtAmpsA, CtAmpsB, and CtAmpsC objects.

See Also

WattNode BACnet – Option CT

 

BACnet Communication	Protocol: BACnet MS/TP (RS-485)
	Baud Rates: 9600, 19200, 38400, and 76800 baud
	Duplex: Half (two-wire plus common)
	Parity (default): N81 (no parity, eight data bits, one stop bit)
	BACnet Buffer: 512 bytes (480 byte maximum APDU length)
EIA RS-485 Interface	Driver Output Voltage (Open Circuit): ± V maximum
	Driver Output Voltage (54Ω load): ± 1.5 V minimum
	Driver Output Current (54Ω load): ± 60 mA typical
	Driver Output Rise Time (54Ω || 50 pF load): 900 nS typical
	Receiver Common-Mode Voltage Range: –7 to +12 Vdc maximum
	Receiver Sensitivity: ±200 mV
	Receiver Bus Load: 1/8 unit load
Electrical	Line powered
	Operating Voltage Range: –20% to +15% of nominal
	Power Line Frequency: 50 or 60 Hz
	CT Input: 0.333 Vac nominal, 0 to 0.5 Vac operating, 3 Vac maximum
Measurement Configurations	Single phase: two or three wire
	Three phase: four wire wye
	Three phase: three wire delta
	Three phase: four wire delta
Accuracy	0.5% nominal
Regulatory	FCC Class B, EN 55022 Class B
	UL and cUL Listed (UL 61010-1)
	CE mark: Declaration of Conformity
	RoHS
Environmental	Operating Temperature: –30°C to +55°C (–22°F to +131°F)
	Altitude: Up to 2000 m (6560 ft)
	Operating Humidity: 5 to 90% relative humidity (RH) up to 40°C, decreasing linearly to 50% RH at 55°C.
	Pollution: POLLUTION DEGREE 2 – Normally only non-conductive pollution; occasionally, a temporary conductivity caused by condensation must be expected.
	Indoor Use: Suitable for indoor use.
	Outdoor Use: Suitable for outdoor use when mounted inside an electrical enclosure (Hammond Mfg., Type EJ Series) that is rated NEMA 3R or 4.
Enclosure	High impact, ABS plastic
	Flame Resistance Rating: 94V-0, IEC FV-0
	Size: 5.63 × 3.34 × 1.5 in. (143 × 85 × 38 mm)
	Weight: 10.8 oz (305 g)
Connectors: Euroblock style pluggable screw terminal blocks	Green: 22 to 12 AWG (1.0 to 3.2 mm), 600 V
	Black: 22 to 12 AWG (1.0 to 3.2 mm), 300 V