WattNode^® MODBUS

WattNode MODBUS

The WattNode MODBUS 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 alternating current VAC and 5 to 6,000 amps in delta (phase to phase) and wye (phase to neutral) configurations.

Measurements

• Supports floating point and integer registers
• True RMS Power - Watts (Phase A, B, C, all phases)
• Reactive Power - VARs (Phase A, B, C, all phases)
• Power Factor (Phase A, B, C, all phases)
• True RMS Energy - Watthours WH kWh (Phase A, B, C, all phases)
• Reactive Energy - VAR-hours (All Phases)
• AC Frequency
• RMS Voltage (Phase A, B, C)
• 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
• 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
• Custom and standard Bus Bar sized CTs
• UL, cUL Listed - Designed and tested for safety and use throughout North America.

WattNode is a registered trademark of Continental Control Systems LLC.

MODBUS Communication

• Protocol: MODBUS RTU (binary)
• Baud Rates: 9,600 and 19,200
  
• Duplex: Half (two-wire plus common)
  
• Parity: N81 (no parity, eight data bits, one stop bit)
  
• MODBUS Buffer: 256 bytes
  
• Response Time: 5 - 300 milliseconds

EIA RS-485 Interface:

• Driver Output Voltage (Open Circuit): ±6 V maximum
  
• Driver Output Voltage (54Ω load): ±1.5 V minimum
  
• Driver Output Current (54Ω load): ±60 mA typical
  
• Driver Output Rise Time (54Ω || 50pF load): 900nS typical
  
• Receiver Common-Mode Voltage Range: -7 V to +12 V maximum
  
• Receiver Sensitivity: ±200 mV
  
• Receiver Bus Load: 1/8 unit load

Certifications

• Emissions: FCC Part 15, Class B; EN 55022: 1994, Class B
• UL and cUL Listed (UL 61010-1)

Electrical

• Line powered
• FCC Class B
• Operating Voltage Range: -20% to +15% of nominal
• Power Line Frequency: 50/60 Hz
• CT Input: 0.333 VAC nominal, 0 - 0.5 VAC operating, 3 VAC maximum

Measurement Configurations

• Three phase: 4 wire
• Three phase: 3 wire

Accuracy

• 0.5% nominal (see manual for details)

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.

Mechanical  Click on the image for a larger view.

• Enclosure:
  • High impact, ABS plastic
  • Flame Resistance Rating: 94V-0, IEC FV-0
  • Size: 143mm × 85mm × 38mm (5.63" × 3.34" × 1.5")
  • Weight: 305 gm (10.8 oz)
• Connectors: Euroblock style pluggable terminal blocks
  • Green: 22 to 12 AWG (1.0mm - 3.2mm), 600 V
  • Black: 22 to 12 AWG (1.0mm - 3.2mm), 300 V

Pricing information for all models and products

Model	VAC Phase to Neutral	VAC Phase to Phase	Electrical Service Types	Neutral Required	MSRP
WNC-3Y-208-MB	120	208-240	1 Phase 2 Wire 120V with neutral 1 Phase 3 Wire 120V/240V 3 Phase 4 Wire 120V/208V		$293
WNC-3Y-400-MB	230	400	1 Phase 2 Wire 230V with neutral 3 Phase 4 Wire 230V/400V		$328
WNC-3Y-480-MB	277	480	3 Phase 4 Wire 277V/480V		$328
WNC-3Y-600-MB	347	600	3 Phase 4 Wire 347V/600V		$354
WNC-3D-240-MB	N/A	208-240	1 Phase 2 Wire 208V (No neutral) 1 Phase 2 Wire 240V (No neutral) 1 Phase 3 Wire 120V/240V 3 Phase 3 Wire 208V (No neutral) 3 Phase 4 Wire 120V/208V		$328
WNC-3D-400-MB	N/A	400	3 Phase 3 Wire 400V (No neutral) 3 Phase 4 Wire 230V/400V		$354
WNC-3D-480-MB	N/A	400-480	3 Phase 3 Wire 480V (No neutral) 3 Phase 4 Wire 277V/480V		$354

List prices for 1 piece quantities. Call for pricing on larger quantities.

Prices effective May 1, 2009. Prices subject to change without notice.

 

Datasheet, Manual, XIF File, and Application Notes

• Datasheet (PDF)
• Manual (PDF)
• Quick Install Guide (PDF)
• Engineering Specifications (DOC)
• Application Notes
• Register List (XLS)

Options

There are currently no options available for the WattNode MODBUS.

 

Options

There are currently no options available for the WattNode MODBUS.