Installation · Growatt

Install GridZeno on Growatt MID 10-25KTL3-X.

MID is a three-phase grid-tied inverter without a battery, so GridZeno can show the production and, where the protocol allows it, limit the export. The dongle is connected with two wires in the round COM connector, pins 3 and 4, which Growatt has set aside for monitoring.

Applies to: MID 10-25KTL3-X and MID 6-12KTL3-XL
Connection: Wires in the inverter's terminal plug
Time: About 25 minutes

A grid inverter without a battery. GridZeno shows solar, consumption and grid and lowers the inverter's export limit at negative prices. What GridZeno can do on Growatt MID 10-25KTL3-X

How the dongle recognises it: The type code 5001. The MID 6-12KTL3-XL isn't in the type table and is recognised by the registers that answer.

GridZeno Dongle for Growatt MID 10-25KTL3-X

What you need

GridZeno Dongle: The device ID is on the label, e.g. GZ-A1B2C3.
Cable: GridZeno's Modbus cable with one end cut off, or another network cable with one plug.
Wire stripper and screwdriver: For the two wires in the signal connector from the inverter's accessory bag.
USB power: A 5 V USB charger and a cable with USB-C.

The port

On the underside of the inverter, to the right of the USB port: the lower of the two round connectors. The upper one is an extra COM connector, which is optional. Two signal connectors come in the accessory bag.

Port: COM (round signal connector)

The COM connector, with the pins numbered as Growatt numbers them. Pins 3 and 4 are for monitoring, pins 5 and 6 for the energy meter. The numbers are on the plug.

Pin 3 A, RS485A1+
Pin 4 B, RS485B1-

The cable

A network cable with an RJ45 plug for the dongle at one end and the other end cut off. At the inverter end, only the two wires from pins 4 and 5 are used. The COM connector has no RS485 GND, so the white/green wire isn't used.

From the dongle to the inverter
Dongle end	Inverter end
Dongle pin 4, blue (A)	COM pin 3, RS485A1+
Dongle pin 5, white/blue (B)	COM pin 4, RS485B1-
The other wires	Cut off and insulated

Settings

On the inverter

General settings > Address setting: 001, as from the factory
Modbus: Modbus RTU at 9600 baud, 8N1. That's what the dongle uses from the factory, so there's nothing to set.

In GridZeno's Welcome

The inverter is chosen in GridZeno: in Welcome the first time, and later under System, Change inverter. The dongle fetches its setup from there.

Manufacturer and model: Growatt, MID
Connection: By cable (RS485)
RS485 settings: Keep the default: 9600 baud, 8N1, address 1.

Step by step

Each step has a small drawing that shows what to do.

1
Check the address
Tap the touch button once to scroll, and twice to select. Go to General settings, past Language settings, to Address setting. It must be 001, as set at the factory.
2
Unplug the COM connector
Switch the inverter off first: switch off the AC breaker, and set the DC switch to OFF. The round connector marked COM is on the underside to the right of the USB port, the lower of the two. Pull it out. If there's no connector, use one of the two signal connectors from the accessory bag.
3
Prepare the cable
Pass the cable through the signal connector's nut and seal. Strip the two wires from pin 4 (blue) and pin 5 (white/blue). Insulate the other wires.
4
Put the wires in pins 3 and 4
Blue (A) goes in pin 3 and white/blue (B) in pin 4, by the numbers on the connector. Don't touch wires in pins 1, 2, 5 and 6: they belong to the dry contact and the energy meter.
5
Plug the connector back in
Plug the signal connector into the port marked COM, and tighten it so it's sealed.
6
Plug the RJ45 end into the dongle
The cable's other end goes into the dongle's RS485 port. Place the dongle somewhere dry and close to the inverter, so the cable doesn't hang from the plug.
7
Connect power to the dongle
Plug the USB-C cable into the dongle and the charger into a socket. The dongle starts by itself. It gets power from the charger, not from the inverter.
8
Connect the dongle to the network
Over Wi-Fi: the first time, the dongle creates its own Wi-Fi, GridZeno-Setup- followed by the last characters of the device ID. Connect your phone to it, choose your own network, enter the password, and press Save and connect. When it says Connection OK, press Go to GridZeno. Over cable (LAN): plug a network cable from the router into the dongle's network port.
9
Log in, and choose your inverter
Log in to GridZeno. Welcome pairs the dongle with its device ID. Then choose your inverter, Growatt MID, and the connection By cable (RS485). Press Save inverter, and the dongle fetches its setup and reads the inverter.

The dongle's own setup is described with screenshots in The user guide, and the pairing in Getting started.

Take care

Pins 5 and 6 are the energy meter's connection and pins 1 and 2 a dry contact. They must not be moved or connected to anything else. DRM uses pins 1 to 6 in the same kind of connector. If the inverter uses DRM, write to us before you connect the dongle.

If you aren't used to fitting wires in a terminal connector, let the installer do it.

What GridZeno can control on Growatt MID 10-25KTL3-X, and how, is on the page about Growatt MID 10-25KTL3-X. If you're stuck, write to us with the model name.

Source

Ports, pins and menus are from the manufacturer's own manual: Growatt MID 10-25KTL3-X Installation & Operation Manual (GR-UM-160-A-02), Sections 3.1, Appearance overview (figure 3.1), 6.4, the signal connector, 9.1.2, Parameter setting, 10.1, RS485, and 10.2, DRM.