Home Energy Monitor

 

ECM-1240 Home Energy Monitor
  • Overview
  • Features
  • Specifications

The ECM-1240 is a multi-channel Energy Consumption Monitor designed for use with residential electrical system.

 

The basic ECM-1240 includes:

  • One ECM-1240 Monitor
  • One Wall Transformer
  • One RS-232 (DB-9) Cable

 

 

 

Features:

  • Multi channels
  • Load Grouping
  • Accurate "True" power measurement
  • Low Cost
 

 

 

 
ECM-1240
ECM-1240 with Wireless and External Antenna Option
 

Note: The specifications listed below may vary depending on firmware changes.
Important Safety Consideration

WARNING!

The ECM-1240 must NOT be installed inside the electrical panel or any other panel possessing "line" voltages.

All signals connected to the ECM-1240 MUST be galvanicaly isolated from the powerline.

The CT installation along with any other task requiring the removal of the electrical panel cover MUST be performed by an electrician or qualified individual. All local electrical codes and rules must be obeyed.

CHANNEL INPUTS

The ECM-1240 consists of two type of power monitoring inputs:

  • CH1 & CH2 Inputs
  • AUXILIARY Inputs (AUX1 to AUX 5)
 
CH1 & CH2 INPUTS
Measurement

Measures "True" or "Real" power based on current and voltage oversampling. The measurements take power factor into account.

Uses automatic gain scaling.

Also measures voltage and current seperately.
Input Signal:

Requires a voltage signal proportional to the input current.

333mV Full-Scale

NOTE: The input signal MUST be galvanicaly isolated from the powerline.
Input Impedance:

20K ohm using the COM and SINGLE terminals.

40K ohm using the COM and DUAL terminals
Max Power Measurement:
 65,535 Kilowatt per channel. (CH1 & CH2)
Max Current Measurement:
 546 Amps based on 120V line voltage
Accuracy:
 Typically +/- 1% plus CT & PT accuracy.
CT Compatibility:

Specifically designed for Brultech's "SPLIT" CTs available for 60A, 100A, 170A, 200A and 400A.

Also compatible with Brultech's Micro CTs with the inclusion of a burden resistor.

Compatible with any CT having 333mV Full Scale and phase error < 2 degrees

CT scaling is configurable to suit the type of CT used.
Energy Measurement:
 Kilowatt-Hour is calculated based on all samples and is updated every second.
Kilowatt-Hour (kWh) Resolution:
 1 Watt-Second
Net Metering:
 Measures directional energy to provide consumed/generated values crucial for net metering applications.
Power Resolution:
 1 Watt
 
AUX1 to AUX5 INPUTS
Measurement
 Measures "True" or "Real" power based on current and voltage oversampling. The measurements take power factor into account.

Input Signal

(AUX1 to AUX4):

Requires a current signal proportional to the input current.

52.46 mA FS

Input Signal (AUX5):

Power Metering:

Requires a current signal proportional to the input current.

52.46 mA FS with external 20 ohm resistor accross the COM and AUX5 terminals.

Pulse Counting:

Dry contact closure between the GND and AUX5 terminals. Contacts must be isolated from outside voltage sources or electrical ground.
   
COMMUNICATION

The ECM-1240 has the following communications ports:

  • One RS-232 Port
  • Optional wireless communication port
RS-232 Port
Connection:
 Terminal strip connection: Common, Transmit, Receive
Baud:
 19,200 Baud (8N1)
   
 
Wireless Communication (optional)
  NOTE: Wireless communication is not WiFi .
Frequency:
 2.4 GHz
Network Type:
 ZigBee mesh network
Transmit Power
 2mW
Antenna:
 Internal wire whip or External 2.1dBi swivel antenna
Sensitivity:
 -96 dBm
Range:

133 Feet* indoors, 400 Feet outdoors (line of sight)

* Range is largely affected by the number of walls the RF signal must travel. The wall density, material and outside interference also affects the range.
Interference Immunity:
 DSSS (Direct Sequence Spread Spectrum)
Baud:
 19,200 Baud
Hardware:
 Digi International's XBee module (www.digi.com)
Firmware:
 Digi International's ZB firmware. (www.digi.com)
   
 
Data Communication
Configuration:
 Uses proprietary binary commands for initial configuration and setup.
Data Output:

Choice of three packet format types:

  1. Binary (standard format)
  2. ASCII
  3. HTTP (requires EtherPort or EtherBee gateway)
Binary Packets:

The is the most common mode of operation. The packet data is configured for efficient data transfer using a proprietary protocol.

Packet Send Frequency: 1 second to 255 second
ASCII Packets:

This format is now offered with newer versions of the firmware to simplify the development of custom software.

Packet Send Frequency: 2 second to 255 second
HTTP Packets:

Using this format along with and EtherPort or EtherBee gateway, packets may be forwarded directly to a web server for processing using HTML, PHP, ASP or other web based languages.

Packet Send Frequency: 10 second to 255 second.
Triggered Packet Send:

Immediate packet send (within one second) for power changes of a defined amount.

Trigger Threshold: 10W to 65kW

*Does not apply to HTTP mode