The emontx V3.4 is the latest version of the emonTx Low Power Wireless Energy Monitoring Node designed for monitoring AC electrical power on (up to) 4 separate (household/building) circuits using non-invasive clip on CT current sensors and an AC-AC Voltage adaptor to provide a voltage signal for full Real Power calculations. The emonTx V3.4 is a minor update over the emonTx_V3
Photo's of emonTx V3.4
New features on emonTx V3.4 over V3 shown in bold
- Measure AC Apparent Power, AC Real power* and AC RMS voltage*
- 3 x single-phase CT current sensor inputs (100A / 24KW @ 240V max)
- 1 x high sensitivity single-phase CT current sensor input channel (18.8A / 4.5KW @ 240V max)
- 1 x RJ45 input for connecting DS18B20 temperature sensors
- Single AC-AC adapter can power the unit and provide AC voltage measurement
- An on-board 3x AA battery option with remote monitoring of battery voltage
- Terminal block access to power rails, digital and analogue I/O and IRQ port for connecting pulse counting sensor / DS18B20 temperature / Aux sensors
- DIP switch selection of RF node ID and 240V/110V AC adapter selection, see #DIP Switch Config
- when AC-AC voltage adapter is connected
Using an ATmega328 microprocessor the emonTx V3.4 runs standard Arduino sketches and is easy to customise and upload code using the Arduino IDE and a USB to UART cable.
The data from the emonTx V3.4 is transmitted via wireless RFM12B / RFM68CW (433/868Mhz) to an emonBase web-connected base-station (we recommend a Raspberry Pi with an RFM12Pi) which then posts the data onto an emoncms server (e.g. http://emoncms.org) for logging, processing and graphing.
DIP Switch Config
The emonTx V3.4 has a couple of DIP switches allowing changing of node ID and setting UK/EU or US AC-AC adapter calibration without having to change the firmware. The unit must be restarted after changing DIP switch positions. Default DIP switch selection (both off) is node ID 10 and 240V AC.