Victron Energy ET112 Energy Meter Manual

1. Introduction

The Victron ET112 is a standard device designed to measure the power and energy consumption of a single-phase application. Its data is displayed on a GX device and the Victron Remote Management (VRM) portal.

1.1. Features

The ET112 can be configured for four distinct roles within a GX device, such as the Cerbo GX:

1. As a Grid meter, used as a control input for an Energy Storage System (ESS).
2. To measure the output of a PV Inverter.
3. To measure the output of an AC Genset.
4. As an AC meter to measure a dedicated AC load circuit.

It offers two connection options to a GX device:

1. A wired connection using the RS485 to USB interface, available with 1.8m or 5m cable lengths.
2. A wireless connection via a Zigbee to USB converter and a Zigbee to RS485 converter.

2. Installation and Configuration

2.1. AC Wiring

2.1.1. Configuration Options

The configuration option (Grid Meter, PV Inverter, Generator, or AC Meter) is set within the GX device. Refer to the GX device configuration chapter for detailed instructions. This selection influences the system's wiring and how meter data is displayed.

Wiring Diagrams:

• Grid Meter Wiring: For use as a grid meter, the diagram shows connections from the grid (L1, L2, L3, N, PE) through an MCB and Fuse to the ET112, and then to an Inverter/Charger.
• PV Inverter/AC Genset Wiring: For measuring PV inverter or AC Genset output, the diagram shows connections from the PV Inverter or AC Genset (L1, L2, L3, N, PE) through an MCB and Fuse to the ET112.
• AC Meter Wiring: For measuring AC output of an Inverter/Charger, the diagram shows connections from the Inverter/Charger (L1, L2, L3, N, PE) through an MCB and Fuse to the ET112, which then connects to AC loads.

2.1.2. System Examples

Example Diagram (ESS with AC PV Inverter):

This configuration uses a single ET112 as a Grid Meter to measure grid import/export in an ESS system with an AC PV inverter. While the PV inverter's exact production isn't directly shown, this setup allows PV production to power non-essential loads on the same circuit.

• Surplus energy charges batteries (seen as export, aiming to reduce grid set point to 0).
• Deficiency triggers battery discharge (seen as import, aiming to reduce grid set point).

This is beneficial for retrofitting Victron ESS systems to existing AC solar inverter installations with loads not connected through the Multiplus. For separate PV production monitoring, the ET340's "single phase dual function mode" can be used.

System Diagram Description: A detailed diagram illustrates a system with Grid, Fuse, MCB, ET112, Inverter/Charger, PV Inverter, RS485 to USB interface, Cerbo GX & GX Touch, Loads, and Critical Loads, showing their interconnections.

2.2. Connection to a GX Device

2.2.1. Wired Connection to a GX Device

Connect the ET112 to the GX device using the RS485 to USB interface. The cable can be extended up to 100 meters. Ensure the Data+ (orange) and Data- (yellow) wires are a twisted pair.

Wiring Table:

The red, green, and brown wires from the RS485 to USB cable are not used and should be cut or insulated.

Connection Diagram: A diagram shows the ET112 connected via an RS485 to USB interface to a Cerbo GX. It notes that an RJ45 plug can be used for connection to the energy meter's RJ45 sockets.

Signal Integrity Notes:

• Ensure extension cabling meets minimum cross-sectional area specifications and has appropriate shielding and twisted pair cores.
• For cable lengths exceeding 10m or in high-interference environments, the original Victron RS485 USB interface cable should be reduced to a maximum of 20cm, using a quality cable for the total length.
• Install cabling away from main DC or AC power cables.
• Ensure all wiring is properly terminated and isolated.
• RS485 networks typically use 120Ω terminators, which may be required for longer or modified cable lengths.
• Refer to the Victron RS485 to USB interface cable Datasheet for detailed notes.

2.2.2. Zigbee Connection to a GX Device

The ET112 can also connect wirelessly to a GX device using a Zigbee to USB converter (connected to GX device) and a Zigbee to RS485 converter (connected to ET112).

1. Connect the Zigbee to USB converter to the GX device. The active LED should be on, and TX/RX LEDs should blink.
2. Connect the Zigbee to RS485 converter to the ET112 terminals:

   Zigbee to RS485	ET112 Terminal Number	Color
   GND	6	Black
   A	4	Orange
   B	5	Yellow

3. Connect the 12V DC power supply to the Zigbee to RS485 converter.

Important: If multiple Zigbee devices are installed, power up only one Zigbee to USB converter at a time to avoid permanent connections to other devices.

Diagram: A diagram shows the wireless Zigbee connection between ET112 and Cerbo GX.

Zigbee Converter Notes: Information on old and new Zigbee converters and their part numbers is provided, noting incompatibility between versions. Minimum Venus OS firmware version for new converters is v2.54.

2.3. GX Device Configuration

After connection and power-up, meters appear in the GX device's Settings → Energy meters menu:

Screenshots: Images show the GX device interface displaying single and multiple energy meters.

After selecting an energy meter, set its Role and Phase type. The interface allows selection of roles like 'Grid meter', 'PV inverter', 'Generator', 'AC load', and phase types like 'Single phase' or 'Multi phase'. The ET112 specifically offers a 'Single phase' option.

Screenshots: Images show the configuration menus for Role and Phase type selection.

The manual details single-phase, single-function, and single-phase, dual-function mode setups.

Screenshots: Images display the configuration for single-phase, single-function and single-phase, dual-function modes, and the resulting data display in the GX device's device list.

Users can access an overview of energy consumption and generation data, and set custom names for meters via the Setup or Device menus.

Screenshots: Images show detailed overview pages and custom name configuration.

2.4. Multiple Energy Meters in One System

To connect multiple Energy Meters, each meter must be wired to a separate RS485 to USB interface, which is then plugged into a distinct USB socket on the GX device. Connecting multiple meters to a single RS485 to USB interface cable is not possible.

ET112 meters can be connected in parallel, but their Modbus addresses must be changed using the supplier's UCS Desktop configuration software, available for free download from the Carlo Gavazzi website.

3. Information on Multiple Zigbee Pairs

3.1. Multiple Zigbee Pairs

Running multiple Zigbee pairs is generally unusual and not recommended due to configuration complexity, especially with Chinese language software. The following applies to new Zigbee converters (DRF2658, DRF2659); older units lack software support.

To operate multiple pairs without interference, each must have a different PAN-Id. Software can be obtained from http://www.dtkcn.com/. The installation software is in Chinese, but the application itself has English translation. Configuration requires wiring an RS485 to USB interface to the RS485 Zigbee module. The USB unit (coordinator) should be configured before powering the RS485 side (router).

Each pair requires a unique PAN-Id.

Using an Energy meter via Ethernet (or Wi-Fi) is a more reliable alternative to multiple Zigbee links.

4. FAQ

Q1: Can I combine three ET112s for a 3-phase system?

No. A dedicated 3-phase meter should be used.

Q2: Can I use other meters, for example from other brands?

No.

Q3: I already have a Fronius SmartGrid meter, can I use that?

No.

Q4: What are the differences between the various 3-phase meters?

Models:

• EM540 - REL200100100 - Carlo Gavazzi EM540DINAV23XS1X
• ET112 - REL300100000 - Carlo Gavazzi ET112-DIN.AV01.X.S1.X
• ET340 - REL300300000 - Carlo Gavazzi ET340-DIN.AV23.X.S1.X

Differences:

• ET meters lack a display, featuring only an LED for communication status.
• ET meters have two RJ45 sockets, but these are not used with the Victron RS485 to USB interface. Screw terminals below the sockets are used for RS485 wiring.
• Due to the lack of a display, Modbus addresses cannot be changed on the meter. This prevents combining multiple meters on one RS485 network without using multiple RS485 to USB interfaces.
• For 3-phase meters: Measuring single-phase PV inverter energy on the second phase of a 3-phase meter is supported.

Q5: Will you keep shipping both 3-phase meters? (ET340 & EM540)

Yes, as both are suitable for different situations.

Q6: Can I buy those meters directly from Carlo Gavazzi instead of from you?

Yes, Victron Energy provides Carlo Gavazzi part numbers.

Q7: I want to use Current Transformers (CTs), is that possible?

Yes. Meters like the CG EM24DINAV53DISX or CG EM530DINAV53XS1X from Carlo Gavazzi are supported in Victron software, though not stocked by Victron.

Q8: What's the difference between ET340 and EM540 in 3-phase systems?

The difference lies in how total imported/exported energy is calculated:

• ET340: Counts energy per phase and sums them for a total.
• EM540: Calculates total power with net differential readings across phases cancelling each other out.

The EM540 is often more suitable for billing in countries like Austria and Germany where only the total is billed, especially when there are phase differentials in generation and load.

Q9: Can I use an isolated USB-RS485 interface?

Victron sells non-isolated interfaces suitable for most cases. For isolated interfaces, purchase from Hjelmslund Electronics (e.g., USB485-STIXL).

Q10: Can I use Victron Energy Meters instead of a Victron Inverter/Charger to make use of a GX device?

Energy Meters supplement Inverter/Chargers and are limited in application, providing specific data like loads or grid import/export. They can be used initially with a GX device to monitor consumption and inform decisions on system sizing (inverters, solar, batteries). With GX device firmware v2.80+, they can measure arbitrary AC loads. However, they are not a replacement for Victron Inverter/Chargers, and attempting to substitute other brands' lack of data connectivity with Energy Meters will not yield expected results.