ET3 - Advanced Power Transducer

The ET3 Advanced Power Transducer adds comprehensive and accurate power monitoring to Control and Energy Management Systems. It may be installed in single, split or three phase configurations. In addition to four analog outputs and one pulse output the transducer offers RS-485 (Modbus) digital communication for monitoring over 20 electrical parameters. An optional Remote Display Module further enhances the ET3 applications.

The ET3 is a precision true RMS power meter and transducer designed specifically for Energy Management applications and Digital Control Systems. It may be used in single, split and three phase installations. The unit may be used for accurate (0.5%) electrical measurements in most power systems, including single phase, split phase, and three phase installations configured in 'wye' or 'delta', with two or three CTs.

The transducer offers four independent 0-5V analog outputs. In addition, energy consumption (Watt-hours) is available as EMS compatible slow pulses (change of state) or 100ms pulses through a solid state relay.

The ET3 is equipped with an RS-485 digital communication port that sends over 20 electrical parameters to a Modbus RTU unit.

The ET3 transducer accepts voltages up to 600 VAC directly, without the need for Potential Transformers (PTs). It supports standard 5A Current Transformers as well as Elkor's line of split core 'safe' CTs. Power line inputs to the transducer are optically isolated from the outputs and the display.

A remote LCD display module (ET3-RDM), may be optionally added to the unit. The display connects to a dedicated output terminal and is powered by the transducer. The display may be mounted in a close vicinity to the ET3 main enclosure or remotely, up to 100 ft (30 m) from the ET3. The display shows selected electrical parameters grouped in a number of screens. The screens may be selected by an easy to use interface.

Elkor offers an inexpensive interfacing solution for power line connections. Our i-block consists of a 'dead-front', ganged fuse holder (for 600 V systems) and CT termination blocks equipped with shorting shunts. All components are DIN rail mounted and ready to wire.

	ET3-1100	ET3-1200
Watt-hour Pulses
RS485 Communications
Remote Display Output (Display extra)
0-5VDC Analog Outputs

OEM version available for greater cost savings!

ET3-RDM: Remote Display Module (Optional)

The ET3-RDM display shows selected parameters in the following screens:

System: System Power Factor Frequency (Hz) Total Real Power (W) Total Apparent Power (VA) Demand (Wd) Energy (kWh)
Power: Real Power, Phase A (W) Real Power, Phase B (W) Real Power, Phase C (W) Apparent Power, Phase A (VA) Apparent Power, Phase B (VA) Apparent Power, Phase C (VA)
Current: Current, Phase A (A) Current, Phase B (A) Current, Phase C (A) Average Current in Three Phases (A)
Voltage: Voltage, Phase A (V) Voltage, Phase B (V) Voltage, Phase C (V) Average Voltage in Three Phases (V)
MAX/MIN: Maximum and Minimum Voltage (V) Maximum and Minimum Current (A) Maximum and Minimum Real Power (W) Maximum and Minimum Apparent Power (VA) Maximum and Minimum Demand (Wd)

Any of the System, Power, Current and Voltage parameters may be viewed in either the multiple display mode (as seen above) or in a large, easy to view font.

Applications:

The ET3 Power Transducer adds new applications to any Energy Management Systems.

The transducer provides building managers and electrical system maintenance personnel with all the data required for proper electrical system management (i.e. feeder load and balance, demand profile, PF correction)
The ET3 can be used as a versatile transducer for complete power metering and monitoring in large and small distribution systems. It can be used to monitor specific electric loads such as chillers, pumps, fans etc. and/or the entire substation.
The ET3 allows the EMS system to identify the electrical load profile and to control the peak demand. This will reduce electricity bills and maximize the benefits of the utility's Time-Of-Use rate schedules.
The ET3 helps monitor and re-distribute utility cost for multi-user organizations. It will add an EMS based electrical sub-metering system for commercial and institutional buildings (campuses, multi-tenant offices, malls etc.).

Specifications:

LINE PARAMETERS:

Voltage:	600 V or 600/347 V (50 or 60 Hz) 480 V or 480/277 V 208 V or 208/120 V Single Phase, Split Phase, Three Phase
Current:	5A from standard CTs or Elkor 'safe' split core MSCT.
All line inputs are optically isolated from the outputs and the display.
Max Ratings:	Voltage: 700 VRMS Current: Twice the nominal value

OUTPUT:

solid state relay (350V, 120mA MAX), change of state or 100ms pulse on every pre-defined Wh value

Analog outputs (0-5V)

The first three analog outputs may be factory configured to represent either:

total real power (W); total apparent power (VA); total real power demand (WD)
Line Voltages - Va; Vb; Vc
Line Currents - Ia; Ib; Ic
Line Real Power - Pa; Pb; Pc

The forth analog output may be configured to reprsent either:

averaged current (Iabc), averaged voltage (Vabc), system power factor (pf), or frequency (Hz).

RS 485 Port

Modbus RTU; up to 64 units may be connected to one 'chain'.

DEVICE SPECIFICATIONS:

Power Supply Requirements:	V=120 VAC or 240 VAC (6 VA max.)
Accuracy:	Better than 0.5% of reading (at 25°C, pf>=0.5) for all measured and calculated parameters.
Environment:	Indoor; 0 to 60°C, 10 to 90°% RH non-condensing. Industrial version -40 to 70°C available.
Warranty:	Full two years manufacturer's warranty.

Ordering Information:

Information:

Datasheet	PDF
Manual	PDF
App. Note AN0302 - RS485 Modbus Addressing	PDF
App. Note AN0303 - Modbus RTU Troubleshooting	PDF
App. Note AN0304 - ET3 Display Port Protocol	PDF
App. Note AN0305 - Introduction to Current Transformers	PDF
Digital Output Wiring Diagram	PDF
3 Wire Delta Wiring Diagram	PDF
4 Wire Wiring Diagram	PDF
Enclosure Diagram	PDF

power meter

wattmeter

power transducer

modbus

rs485