eGauge Overview

eGauge is an affordable, flexible, secure, web-based electric energy and power meter that can measure up to 12 circuits on up to 3-phases (120V−480V, 50−60Hz). Use it to measure and record whole-house consumption, solar, wind, and other renewable electricity generation, measure consumption of individual loads, such as appliances or the consumption of geothermal system pumps and backup heaters. The data can be viewed on any web-enabled device through the built-in web-server. The display is updated every second, giving immediate feedback on any load or generation changes. The device records the most recent 30 years of data in its built-in solid-state memory. The measurements can also be accessed through BACnet and/or can be pushed to a server via our XML API.

The eGauge3 Series comes in two models: EG300x and EG301x. The EG300x must be connected to the network via the built-in Ethernet port, while the EG301x has both HomePlug and Ethernet-direct communication capabilities.


Installing an eGauge often pays for itself in a short amount of time.

Optimize your carbon footprint

Track your usage and compare it on a single screen to your renewable energy generation, helping you achieve net-zero energy consumption, maximize your payback, and lower your monthly electricity bill.

Lower your peak demand

With second by second updates, you will immediately see major loads turning on and off. Giving you the tools needed to minimize peaks.

Monitor your system health remotely

Since eGauge is accessible through the Internet at no extra charge, you can easily check on your home and/or renewable energy system while travelling.

For renewable energy-system installers, our eGuard Manager service provides a convenient way to monitor all your installed systems on a single screen and detect failures even before your customers do.

Measure individual appliances

Use a single eGauge to meter up to twelve separate circuits or gang multiple eGauge together for virtually unlimited capacity. Measure individual loads (AC, fridges, geothermal pumps), individual apartments, hotel-rooms, etc.

Hardware Components

EG301x HomePlug Enabled

Please note, hardware shown for EG301x. The EG300x does not support HomePlug communication and must be installed in a separate enclosure, connected via Ethernet to the network. The EG301x supports both Ethernet-direct and HomePlug communication.

Metering Capabilities

eGauge samples each measurement channel several thousand times a second in order to calculate real power (what the utility bills you for), apparent power, True RMS voltage, and current. The high-frequency and simultaneous sampling allows eGauge to establish the phase-relationship between the voltage and current channels and therefore it can detect which direction power is flowing (e.g., from grid to house, when power is being consumed, or from house to grid, when renewable-energy generation is greater than usage in the house).

Once a second, eGauge updates the following quantities:

The eGauge web interface provides a live view of these quantities through the channel checker (Tools→Channel Checker).

The eGauge Web Interface

The main screen of the eGauge web interface presents current consumption and generation info with a live, high-resolution graph:

Snapshot of eGauge Web Interface

The left portion of the graph displays recent historical data (most recent 24 hours in the example above), whereas the right portion is a gauge that is updated each second and displays current generation (green) and consumption (red). In the example above, at the time the snapshot was taken, the solar system was producing 7742 Watts of power while total consumption at the house was 1478 Watts.

The thick red line indicates total consumption whereas the thick green line indicates total generation. The red shaded area indicates the amount of energy consumed from the grid whereas the green shaded area indicates the amount of energy put back onto the grid.

Kiosk View

By clicking on the "View" link at the top right of the main screen, on can select multiple informative views for the device. The kiosks are designed for non-interactive displays such as an entry-lobby or a kitchen tablet computer. The "Bunny Kiosk" automatically cycles through three screens: the first screen shows renewable energy generation since midnight. The second screen shows renewable energy generation since the eGauge was installed. The third screen shows a simplified version of the graph that is shown on the main screen.

Bunny kiosk-view of eGauge Web Interface

The "Sleek Kiosk" display is a one-screen summary for the last three days. The comparison values provide some interesting conversions for energy production such as homes powered and miles driven, and the graph is set to the three day display by default. Preferences may be changed to allow different time lengths to be displayed, and choose the lower two conversions from a pre-set list.

Sleek kiosk-view of eGauge Web Interface

For a fee, the kiosk-view (as well as other aspects of the Web interface) can be customized. For example, the screenshot below shows a customized kiosk interface created for Creative Energies:

Creative Energies Web Interface

Web-based Configuration

Virtually every aspect of an eGauge's operation can be configured through the web-interface. Access to these screens is protected through a password that needs to be entered before saving any changes.

The screenshot below shows the Installation screen, which defines what kind of CTs are connected to the eGauge, what energy data (Registers) to record, and how total consumption and generation are to be calculated:

eGauge Settings Screen

A technical data sheet of eGauge's specifications is available here. For more information on configuration options, see the eGauge Configuration Guide, available in the Support Section of this web site. For security and access information please see our Security Considerations page.


For building automation and control, eGauge supports the BACnet protocol. Using the eGauge BACnet setting screen (Settings→BACnet), the BACnet device id can be selected and eGauge can configured to use either the BACnet/IP (BIP) or BACnet/Ethernet data-link layers.

eGauge provides access to the current (second-by-second) measurements through the following Analog Input object groups:

Group Number: Number of first object in group: Description:
10x20000: Voltage [V].
20x30000: Current [A].
30x50000: Line frequency [Hz].
40x60000: Timestamp [s].
50x70000: REGVAL [various].
60x80000: REGCHG [various].

Group 1
The RMS voltage of the voltage-taps can be read through this group. Object ID 0x20000 corresponds to L1, 0x20001 to L2, and 0x20002 to L3.
Group 2
The RMS current measured by each CT can be read through this group. Object ID 0x30000 corresponds to CT1, 0x30001 to CT2, and so on, up to 0x3000b for CT12.
Group 3
The frequency of the voltage-taps can be read through this group. Object ID 0x50000 corresponds to L1, 0x50001 to L2, and 0x50002 to L3.
Group 4
0x60000 is the only valid object ID in this group and it reports the number of seconds elapsed since the BACnet daemon was started up. The BACnet daemon starts up either after freshly enabling BACnet support or after power-cycling or rebooting eGauge.
Groups 5 and 6
In these groups, the first few object IDs refer to the virtual registers (including totals), one per virtual register. This usually includes "Total Usage" and "Total Generation", along with any other virtual registers defined in the "Totals and Virtual Registers" section of the Settings→Installation screen. Subsequent object IDs correspond to the physical registers as defined in the "Registers" section of the eGauge Installation screen. The register name for a given object ID can be obtained by reading the "name" property (BACnet property 85) from the object ID.

Group 6 reports, for each virtual and physical register, the change in register value during the most recent one-second interval. The physical unit of this register depends on the quantity being recorded and can be obtained by reading the "unit" property (BACnet property 117) of the respective object id. For example, for a register recording power, the unit would be Watts, for a register recording voltage, the unit would be Volts.

Group 5 reports the register value for each register (virtual and physical). The register values are time-weighted values and hence the unit of these object IDs is equal to the unit of the corresponding object ID in Group 6, multiplied by seconds. For example, for a register recording power, the Group 6 unit would be Watts, and therefore the Group 5 unit would be Watt-seconds (i.e., Joules).