Latest revision as of 19:46, 19 October 2016

EmonWRT Wifi Energy Monitoring Device with OpenWRT

EmonWRT is a one unit system for energy monitoring. It measures usage of an electrical installation and post data on a server (Emoncms). You can then view the data on your computer or phone.

It combines the Arduino based microcontroller and OpenWRT wifi module together. EmonWRT interfaces with sensors like Current Transformers/ Temperature and Voltage.

The EmonWRT is currently for sale here.

Simple to use with web interface for configuration.
Connect with Wired or Wifi.
Wall mountable.
Single box system.
Open source components OpenWRT and Arduino.

EmonWRT vs Raspberry Pi. The main motivation for developing the EmonWRT was to increase robustness. For the long run the RaspberryPi solution can become vulnerable due to the operating system hosted on a SD card. High quality SD cards can be used but a higher risk of failure still remains. The EmonWRT contains the operating system on an embedded flash memory and will solidly keep on running.

Technical Specifications

4 Current Sensor Ports
1 Temperature Sensor Port
3 AC/AC Adaptor Port

1 Ethernet Port
1 MicroUSB Power Supply port

Operating System: OpenWRT Barrier Breaker
Micro Controller Unit: Attiny84 (Arduino)
Current Sensor burden resistor: 24Ω
Wifi (internal antenna)
Dimensions: 106x86x19mm

Recommended Sensors

Current: SCT-013-000
Temperature: DS18B20
AC/AC Adaptor: 77DB-06-09 77DE-06-09 77DA-10-09

Defaults

IP Address (LAN): 192.168.2.1
IP Address (WAN): DHCP
Username: root
Password: admin

Hardware

Internally the Arduino mcu collects data from sensors on the ADC port and transmit them to the OpenWRT module via serial interface.

Then the OpenWRT module transfer all data to the specified web server (Emoncms, thingspeak etc...) using conventional ethernet protocols.

The Arduino sketch can be uploaded to the board for custom applications. The default sketch is available on this page.

The configuration of the unit is quite simple using the Luci web interface that comes with OpenWRT. One can at easy configure the EmonWRT to connect to a home wireless router.

Configuration

The web interface

OpenWRT uses Luci for configuration. The EmonWRT has a page on Luci where APikey, emoncms server and node ID can be configured.

Apikey is the long number that identify the account on the Emoncms server. It can be found on the emoncms server in the API help page. The Read & Write apikey key should be copy pasted here.
EmonCMS Hostname is the location of the emoncms server to use. It can either be emoncms.org or your own server. If using your own emoncms server you might need to indicate the full path here. e.g. 192.168.1.50/emoncms/
Node ID is a number that identify the device. If you have several EmonWRT (or emontx) you can change this number here to differentiate between them on the server.

Background Configuration

The actual configuration is saved in a text configuration file /etc/config/emonwrt.

Arduino Sketch

The emontx has an attiny84 mcu which can be programmed with the Arduino IDE. To upload a sketch you will have to open the EmonWRT box and connect an avr programmer to the SPI port on the EmonWRT. The default arduino sketch can be found on this page. The library from OEM is also needed for this. It can be found here.

Serial String Format

If you decide to write your own sketch you need to output on serial interface the data in the following format:

EMONWRT CSV_DATA

CSV_DATA being each output field separated by a comma. Here is an example for three fields:

EMONWRT 75,45,4058
EMONWRT 79,51,4060

This format is necessary for the forwarder program in the WR703N.

Data Forwarder script

The WR703N router has a script written in bash to grab the data from the ARduino mcu and send them over to the emoncms server. This script is called emonwrt_forwarder.sh. You can download it below.
The script is launched when OpenWRT boots up using init.d mechanism.

RF Gateway

Previous version of EmonWRT used to have RF gateway. Due to lack of interest we have removed this option. Get in touch with us if you need a similar solution.

Files

Default Attiny84 Sketch

Howtos

Startup Guide

(old) Install/Update EmonWRT on WR703N

(New) Install/Update EmonWRT on WR703N

Start the forwarder in debug mode

Upload Firmware

Timeout for some wifi connections

Version History

Sketch

1.6

EmonWRT Software

1.3

Support for OpenWRT Attitude Adjustment

1.4

Support for OpenWRT Barrier Breaker

@@ Line 1: / Line 1: @@
+[[Image: IMG_0859_small.jpg | right]]
-=EmonWRT Wifi Energy Monitoring Device with OpenWRT and Emontx.<br />=
+=EmonWRT Wifi Energy Monitoring Device with OpenWRT<br />=
 '''''<br />'''''
@@ Line 11: / Line 13: @@
 It combines the Arduino based microcontroller and OpenWRT wifi module together. EmonWRT interfaces with sensors like Current Transformers/ Temperature and Voltage.
-This is a powerful system for a small installation like a domestic house with an access to the internet. <br />
-[http://lechacal.com/shop/?16,emonwrt The EmonWRT is currently for sale here.]
+[https://lechacal.pswebshop.com/internetofthing/13-emonwrt2-energy-monitoring-wifi-openwrt-emoncms-thingspeak-3phase.html The EmonWRT is currently for sale here.]
 [[Image:diagram_small.png|directct1temp1]]<br />
@@ Line 28: / Line 30: @@
-[[File:Ports_details_v1.0.png | right]]
+[[File:IMG_0856_small.jpg | right | 400px]]
-* 3 Current Sensor Ports
+* 4 Current Sensor Ports
 * 1 Temperature Sensor Port
-* 1 Pulse Counting Port
+* 3 AC/AC Adaptor Port
-* 1 AC/AC Adaptor Port
-* 1 FTDI port (internal)
-<br />
 * 1 Ethernet Port
-* 1 USB port
 * 1 MicroUSB Power Supply port
-<br />
-* Operating System: OpenWRT 12.9 Attitude Adjustment
+* Operating System: OpenWRT Barrier Breaker
-* Micro Controller Unit: Atmega328 (Arduino Bootloader)
+* Micro Controller Unit: Attiny84 (Arduino)
-* Current Sensor burden resistor: 24Ω (or 18Ω)
+* Current Sensor burden resistor: 24Ω
-* Wifi Specifications: See TP-link WR703N
+* Wifi (internal antenna)
-* Dimensions: 70x62x35mm <br />
+* Dimensions: 106x86x19mm <br />
 ===Recommended Sensors===
 Current: SCT-013-000 <br />
 Temperature: DS18B20<br />
-Pulse Detector: TSL257<br />
+AC/AC Adaptor: 77DB-06-09 77DE-06-09 77DA-10-09
-AC/AC Adaptor: 77DB-06-09
 ===Defaults===
@@ Line 59: / Line 57: @@
 =Hardware=
-The WR703N wifi routers is used to connect to the home router (wired or wireless) and forward the data to an Emoncms server such as emoncms.org<br /> The two units are connected together with serial interface.
-[[Image:Wr+emontx crop.png|900px]]<br />
+Internally the Arduino mcu collects data from sensors on the ADC port and transmit them to the OpenWRT module via serial interface.
+Then the OpenWRT module transfer all data to the specified web server (Emoncms, thingspeak etc...) using conventional ethernet protocols.
-===EmonTX: The sensor node module===
-The EmonWRT uses the open source EmontX V2.2 from [http://openenergymonitor.org openenergymonitor.org] as sensor interface. The only difference is the RF module not being installed. It's not needed and keeps cost down.
+The Arduino sketch can be uploaded to the board for custom applications. The default sketch is available on this page.
-The sketch can be uploaded to the board to work for the application that you need. This is a default [http://lechacal.com/EmonWRT/EmonWRT_CT123_T_v1_5.ino sketch] to work with CT123 and temperature together.
-A quick overview of the Emontx V2<br /> * 3 Current transformer ports.<br /> * 1 Temperature port (DS18B20).<br /> * 1 Interrupt port.<br /> * 1 AC Adaptor.<br /> * 1 FTDI port for flashing the mcu.<br />
+The configuration of the unit is quite simple using the Luci web interface that comes with OpenWRT. One can at easy configure the EmonWRT to connect to a home wireless router.
-More info on the Emontx [http://openenergymonitor.org/emon/emontx here]
-===WR703N Wifi Router===
-The TP-LINK WR703N Wifi router runs with OpenWRT operating system.
-The configuration of the router is quite simple using the Luci web interface that comes with OpenWRT. One can at easy configure the router to connect to a home wireless router.
-Emontx and WR703N communicates together using serial communication with /dev/ttyATH0
 =Configuration=
@@ Line 107: / Line 89: @@
 ==Arduino Sketch==
-The emontx has an atmega328 which can be programmed with the Arduino IDE. To upload a sketch you will have to open the EmonWRT box and connect a FTDI/USB cable to the FTDI port on the emontx.  The default arduino sketch can be found [http://lechacal.com/EmonWRT/EmonWRT_CT123_T_v1_4.ino Here]. The library from OEM is also needed for this. It can be found [https://github.com/openenergymonitor/EmonLib here]. This sketch will output three current sensors (CT1 2 and 3) and temperature.<br /> <br />
+The emontx has an attiny84 mcu which can be programmed with the Arduino IDE. To upload a sketch you will have to open the EmonWRT box and connect an avr programmer to the SPI port on the EmonWRT.  The default arduino sketch can be found on this page. The library from OEM is also needed for this. It can be found [https://github.com/openenergymonitor/EmonLib here].<br /> <br />
 ===Serial String Format===
@@ Line 124: / Line 106: @@
 ===Data Forwarder script===
-The WR703N router has a script written in bash to grab the data from the EmonTX and send them over to the emoncms server. This script is called emonwrt_forwarder.sh. You can download it below.<br />
+The WR703N router has a script written in bash to grab the data from the ARduino mcu and send them over to the emoncms server. This script is called emonwrt_forwarder.sh. You can download it below.<br />
-The script is launched when the WR703N boots up using init.d mechanism.
+The script is launched when OpenWRT boots up using init.d mechanism.
 =RF Gateway=
-The EmonWRT can optionally be used as a gateway for other RF sensors. Using the RFM12B module the EmonWRT will read and receive all data from other sensors equipped with the same module (other emontx, emonTH, tinyTX etc...).<br />
+Previous version of EmonWRT used to have RF gateway. Due to lack of interest we have removed this option. Get in touch with us if you need a similar solution.
-To enable the RF forwarding from your sensor to EmonCMS one should set the RF variable to 1 in the Arduino sketch.<br /><br />
-Internally the emontx inform the forwarder script using a RFNODE header in the serial string. The format is as follow:<br/>
- RFNODE <node_ID> <csv_DATA>
-For example with a node ID 10 the string will look like:
- RFNODE 10 165,0,0,2781
- RFNODE 10 168,0,0,2781
 =Files=
-[http://lechacal.com/EmonWRT/EmonWRT_CT123_T_v1_6.ino Default EmonTX Sketch - Ct123 & Temperature]<br />
+[http://lechacal.com/EMONWRT2/EmonWRT2_default_attiny_v1_0.ino Default Attiny84 Sketch]<br />
-[http://lechacal.com/EmonWRT/system/v1.3/emonwrt_forwarder.sh emonwrt_forwarder.sh ]<br />
-[http://lechacal.com/EmonWRT/system/v1.3/config/emonwrt Configuration file]
 =Howtos=
@@ Line 151: / Line 121: @@
 [[Startup_guide_emonwrt | Startup Guide]]
-[[update_emonWRT| Install/Update EmonWRT on WR703N]]
+[[update_emonWRT| (old) Install/Update EmonWRT on WR703N]]
+[[update_emonWRT_from1.5 | (New) Install/Update EmonWRT on WR703N]]
 [[forwarder_debug| Start the forwarder in debug mode]]
-[[FIRMWARE_UPLOAD| Upload Firmware]]
+[[FIRMWARE_UPLOAD_EMONWRT2 | Upload Firmware]]
 [[Timeout for some wifi connections]]
@@ Line 170: / Line 142: @@
 ===1.4===
 * Support for OpenWRT Barrier Breaker
+[[Image: IMG_0849_small.jpg]]

EMONWRT2: Difference between revisions