Deye SUN-SMART-TX01: How to Set Up Smart TX Without Confusion

The Deye Smart TX is a small LoRa communication node, but many installation problems start when it is mistaken for a meter, a Wi-Fi logger or a stand-alone controller.

Quick answer

SUN-SMART-TX01 is not a meter. It is the Smart TX transmitter used to link Deye hybrid inverters with Deye smart devices over LoRa, such as Smart CT, Smart Switch, Smart Plug and selected EV charger functions. In a typical metering setup, Smart CT measures the grid side, sends data wirelessly to Smart TX, and Smart TX passes the data to the inverter through the Meter/COM connection.

Why customers often get stuck

Most Smart TX problems are not caused by a faulty product. They usually come from a misunderstanding of what the device is supposed to do.

Customers may expect SUN-SMART-TX01 to act like a Wi-Fi dongle, a cloud data logger or the main electricity meter. In practice, it is the communication bridge in the Deye wireless energy management system. It sits at the inverter side and helps the inverter receive information from Deye smart devices over LoRa.

Once this role is clear, the rest of the setup becomes easier: power the Smart TX, connect it to the correct inverter port, enable the relevant smart device in the inverter menu, and make sure the LoRa channel and serial number are correct.

What Smart TX actually does

Smart TX is the main communication node between the inverter and wireless Deye smart devices. Its most common use is with Deye Smart CT, where it helps deliver grid import and export data to the inverter without a long RS485 cable between the distribution board and the inverter.

The basic data path is simple: Smart CT measures the grid side, sends data through LoRa, Smart TX receives the LoRa signal, and the inverter reads the information through the Meter/COM port.

Because of this, Smart TX does not replace Smart CT. The CT measures. The TX transmits. The inverter controls.

When Smart TX is useful

Smart TX is useful when the inverter and the meter position are far apart, when running a communication cable is difficult, or when the project also uses Deye smart load devices.

It can also help installers keep the system cleaner. Instead of extending communication wiring across a home or small commercial site, Smart TX provides a wireless link for supported Deye devices.

Before installation, confirm that the inverter supports the Smart Devices function. On some inverter models or older hardware versions, the Smart Devices menu may require a firmware update or may not be available.

Before you start

Prepare the Smart TX unit, the communication cable supplied with the accessory package, and an external 5 V USB-C power supply if the inverter Meter/COM port cannot supply 5 V DC.

Write down the serial number of the Smart CT or other smart device before you close the cabinet. The serial number is normally needed when adding the device in the inverter menu.

Installation should be carried out by a qualified person. Do not open or wire live electrical equipment. Follow the inverter manual, local electrical rules and the project wiring diagram.

Installation: the three checks that matter

Fit Smart TX at the inverter side: Unscrew the sealing cover of a suitable COM inlet on the inverter and fix Smart TX to that inlet. Do not leave the device hanging loose outdoors or exposed in a way that could reduce protection after installation.
Connect the communication cable: Use the supplied cable to connect the inverter Meter/COM port to the RJ45 port of Smart TX. Make sure it is the meter communication port, not the LAN, data logger or unrelated network port.
Provide stable 5 V power: Some inverter ports can power Smart TX directly. If the port cannot output 5 V DC, connect the Type-C port of Smart TX to an external 5 V USB power source.
Keep the LoRa path realistic: Deye lists a barrier-free LoRa communication distance of about 200 m. Real buildings reduce that range. Thick walls, metal cabinets, EV chargers, frequency converters and other electromagnetic interference sources can weaken the signal.

Set up the inverter menu

From the inverter LCD, go to System Setup and then Smart Devices. This is the key menu for Smart CT, Smart Switch, Smart EV Charger and Smart TX.

If Smart Devices is missing, do not keep changing cables at random. The inverter may need a firmware update, or the hardware version may not support the function. Contact after-sales support with the inverter model and firmware information.

For Smart CT, open the Smart CT page, enter the serial number from the device label, and enable the correct CT position. CT1 is normally used for the wireless CT meter at the grid connection point. CT2 is used for a wireless CT meter on the on-grid inverter side where that system design applies.

After entering the serial number, perform the required channel scanning or matching step so the Smart CT and Smart TX communicate on the same LoRa channel.

Use the Smart TX page only when you need to check or reset the transmitter. Resetting Smart TX restores factory settings, returns the communication channel to the default channel, and clears bound sub-device information. Do this only when needed.

How to know the system is working

The inverter should stop showing meter connection errors and should display grid power, load power or import/export changes that respond to real household consumption.

The LoRa and RS485 indicator lights on Smart TX help with the first diagnosis. In normal communication, the relevant indicator flashes at one-second intervals. A steady light indicates that no communication is detected. Faster flashing can occur during firmware upgrading.

Check the inverter screen and, where available, Deye Cloud after commissioning. If the inverter values change when loads turn on or off, the communication chain is likely working.

Common problems and what to check first

Problem seen by customer	Likely cause	First action
Smart TX has no sign of power	Meter/COM port is not supplying 5 V, or the cable/power source is wrong	Use a stable 5 V USB-C supply and check that the TX is properly seated and connected.
Smart Devices menu is missing	Inverter firmware or hardware does not support the feature	Record the inverter model and firmware version, then contact after-sales support for confirmation or upgrade.
Inverter says meter is not connected	Wrong port, loose RJ45 cable, wrong meter setting or disabled grid metering	Check Meter/COM cable, confirm meter settings, restart TX and inverter after changes.
Smart CT is enabled but no data appears	Wrong serial number, channel mismatch, CT not powered or LoRa signal is weak	Bring CT and TX closer for commissioning, re-enter serial number, scan channel again, and check CT power.
Power flow is reversed or looks wrong	CT direction, phase order, CT ratio or voltage sampling is incorrect	Check CT arrow direction, CT ratio settings and phase/voltage wiring before changing inverter logic.
Data disconnects frequently	Poor signal path, metal obstruction, interference or unstable 5 V power	Move Smart TX or CT position, avoid metal cabinets and strong interference, and use a reliable 5 V adapter.
System worked before a channel change	Linked devices are no longer on the same LoRa channel	Use the Smart TX and smart device menus to align the channel again, or reset and recommission if necessary.

The mistakes we see most often

Calling Smart TX a meter. It is a transmitter; Smart CT or another smart device provides the measured data.
Connecting the cable to the wrong port. The TX must connect to the inverter's meter communication path, not to a normal network port.
Forgetting the 5 V supply. If the inverter port does not power the device, Smart TX needs external USB-C power.
Typing the wrong serial number. One wrong digit can stop pairing even when the wiring is correct.
Expecting the advertised wireless distance in a metal cabinet or behind thick walls. The 200 m figure is a barrier-free reference.
Changing the LoRa channel before understanding what is already paired. Channel changes can break communication until all devices are aligned again.

Frequently asked questions

Does SUN-SMART-TX01 replace SUN-SMART-CT01?

No. Smart CT measures electrical data. Smart TX helps send the data to the inverter.

Does Smart TX need the internet?

No for local LoRa communication with the inverter. Internet is only needed for cloud monitoring or remote platform functions.

Can Smart TX work with non-Deye inverters?

It is designed for the Deye wireless energy management ecosystem. Use it with compatible Deye hybrid inverters and supported smart devices.

What should I do if pairing fails?

Check power, distance, serial number and LoRa channel first. Then restart the smart device, Smart TX and inverter. If the menu is missing, check firmware support.

When should I reset Smart TX?

Reset only when the device was previously bound to other smart devices, the LoRa channel is confused, or normal recommissioning does not restore communication.

A simple rule for support teams

When a customer calls about Smart TX, follow the communication chain instead of guessing:

Is the inverter compatible and does it show the Smart Devices menu?
Is Smart TX powered by the inverter port or by a stable 5 V USB-C supply?
Is the RJ45 cable connected to the correct Meter/COM port?
Is the smart device serial number entered correctly and enabled?
Are Smart TX and the smart device on the same LoRa channel?
Do the live inverter readings change when real loads turn on or off?

Bottom line

SUN-SMART-TX01 is a small device, but it plays an important role in Deye wireless energy management. It is best understood as the inverter-side communication bridge. Once installers and customers remember the path - smart device to LoRa, LoRa to Smart TX, Smart TX to Meter/COM port, and then to the inverter - most setup issues become easy to isolate.

For projects using Deye hybrid inverters, Smart CT, Smart Switch, Smart Plug or compatible smart charging functions, Uni Z International B.V. can help confirm the right accessory combination before installation.