VARTA element (pv)
The VARTA element (pv) is a residential AC-coupled battery storage system used in solar self-consumption installations alongside separate PV inverters. This template reads register 1102 over Modbus TCP, exposing the real-time PV generation power as measured by the VARTA external PV sensor input. Supported devices include the pulse, pulse neo, element, and element backup. Connecting VARTA to the ModbusCloud Gateway gives installers and building owners a live view of on-site solar generation directly in the portal without manual data exports.
- Protocol
- Modbus TCP
- Connection
- Ethernet, Modbus TCP
- Registers
- 1, read only
- Brand
- VARTA
- Compatible models
- pulse · pulse neo · element · element backup
- Last updated
Registers (1)
1 read, 0 write
| Name | Unit | Access | Address (Hidden until you enter your email) | Function (hidden) | Type (hidden) |
|---|---|---|---|---|---|
| power | W | Read |
Loading registers…
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Use cases
- Monitor live PV generation power to verify sensor wiring is correct after installation.
- Track PV output trends over days to detect soiling or shading on specific strings.
- Alert on unexpected drops in PV sensor readings during daylight hours to spot sensor faults.
- Compare PV sensor readings against inverter output data to validate measurement accuracy.
- Report daily PV generation figures to building owners or energy managers from the portal.
Installation
Confirm that a VARTA PV sensor (split-core current transformer) is physically wired to the second sensor input on the storage unit, as register 1102 only returns data when this hardware sensor is present and active.
Connect the VARTA storage unit to the same LAN as the ModbusCloud Gateway using an Ethernet cable, and note the unit's IP address assigned by your router or set statically.
In the ModbusCloud portal, add a new device, select the ModbusCloud Gateway, import the VARTA element (pv) template, set the host to the unit's IP address, port 502, and unit ID 255.
Spot-check the power register in the live data view during daylight hours: the value should reflect actual PV generation in watts. A persistent zero during sunshine indicates the PV sensor is not connected or the unit does not support this register.
Things to watch for
Register 1102 always returns zero during daylight. Why?
Register 1102 only outputs data when PV generation is measured by the VARTA external PV sensor input (split-core current transformer on the second sensor port). If your inverter feeds PV data to the VARTA unit via SunSpec over the network, that data is not reflected in register 1102. Verify the physical sensor is installed and connected.
The gateway connects to the VARTA but then loses connection repeatedly.
The VARTA Modbus TCP server can drop idle connections. ModbusCloud polls at most once per minute, every 5 minutes by default, so one-second polling to keep the session open is not possible. Avoid simultaneous Modbus TCP connections from multiple clients, such as a home automation system and the Gateway at the same time, as the VARTA server handles only one active session reliably.
Why do I receive an 'illegal data address' error for register 1102?
Not all VARTA element variants expose register 1102. The element and element backup models may return exception code 2 if the PV sensor option is absent or a firmware update is pending. Confirm the physical PV sensor accessory is installed, and check VARTA's published Modbus documentation for your exact model generation.
Which unit ID should I use when configuring the VARTA in the portal?
VARTA's official Modbus documentation recommends unit ID 255 as the default for all supported models including the pulse, pulse neo, element, and element backup. If reads fail with 255, try unit ID 1, as some firmware versions respond on both addresses. Confirm in the VARTA web interface under the communication or network settings section.
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