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Compatibility · Ready for GridZeno

Sofar KTLX 25-136 kW with GridZeno.

A grid inverter without a battery. GridZeno shows solar, consumption and grid and lowers the inverter's export limit at negative prices. Applies to 25-50KTLX-G3, 60-80KTLX-G3, 100-125KTLX-G4, 100-136KTL-PRO and 75-136KTL-HV.

01

What GridZeno can do on Sofar KTLX 25-136 kW

Sofar KTLX 25-136 kW on the compatibility list, updated 31 October 2026.

  • Live overview of solar, consumption and gridAll subscriptions · Grid and consumption require an energy meter at the grid connection.
    Works
  • Battery state of chargeAll subscriptions · requires a battery · The grid inverter has no battery.
    Not possible
  • Stop selling at negative pricesSmart and Pro · Requires the installer to have turned export limiting on in the inverter. GridZeno only lowers a limit that's already set. Also requires inverter firmware from 2022 or later.
    Works
  • Charge from the grid when power is cheapSmart and Pro · requires a battery
    Not possible
  • Discharge the battery when power is expensivePro · requires a battery
    Not possible

Works: tested and measured on real hardware.

02

How the inverter is controlled

A grid inverter without a battery: GridZeno reads it and lowers the export limit at negative prices.

Battery
None. The inverter is a grid inverter without a battery, so there's nothing to charge or sell from.
Stop selling at negative prices
The inverter's export limit is set quarter by quarter by the selling price, but only where the installer has turned export limiting on. GridZeno only lowers a limit that's already set and never turns it on or off.
What it requires
Inverter firmware from 2022 or later for the export limit, and an energy meter at the grid connection for grid and consumption.
Manual
When the control is on Manual, the dongle changes nothing on the inverter. It reads, and if GridZeno has changed something, it puts the inverter's own settings back, including your own charge limits.
03

What is special about the Sofar KTLX 25-136 kW

The serial number in holding 0x0445 with the code S3 (25-50KTLX-G3), S4 (60-80KTLX-G3) or Q1 (75-136KTL). A 20-character serial number with the code 036 is 100-125KTLX-G4.

The sun
Up to 16 channels from 0x0584, only those the address mask 0x0580 shows.

How it differs from its neighbours

  • Sofar KTLX: The KTLX-G3 up to 24 kW has the codes S1 and S2 and is read and limited the same way.
  • Sofar 250-350 kW, 800 V: The 250-350 kW park inverters have the code R1 and are also read the same way.

For the installer: the registers

What the dongle uses over Modbus, if you want to follow along or troubleshoot. Don't change the registers yourself while control is set to Automatic.

Serial number
0x0445, and characters 17-20 of a 20-character serial number in 0x0470-0x0471.
Export limit
0x1023 and 0x1024 in 100 W. Only in the installer's modes 1 and 2; in modes 3 and 4 and in parallel operation it's only read.
Rated power
0x06ED in 0.1 kW.
Fault codes
30 words in 0x0405-0x0416 and 0x0432-0x043D.

From the dongle's firmware and our notes on each inverter, not from the datasheet.

04

How to connect the dongle

Wires in the inverter's terminal plug. Approx. 30 minutes.

Port
COM (16-pin connector, RS485 Modbus/DRMs)
Pin
A at pin 1 (RS485 A), B at pin 3 (RS485 B), GND at pin 7 (GND.S)
Where
On the underside of the inverter, by the USB port. On 100-125KTLX-G4 the port is called COM1. The same connector is used for energy meter and DRM, so there may already be wires in it.

See the full installation guide for Sofar KTLX 25-136 kW

GridZeno Dongle for Sofar KTLX 25-136 kW

05

Before you buy

This one works.

Sofar KTLX 25-136 kW is the inverter GridZeno has been tested on. Check that your model is under 25-50KTLX-G3, 60-80KTLX-G3, 100-125KTLX-G4, 100-136KTL-PRO and 75-136KTL-HV. If it still doesn't suit you, you have 100 days' free return.