Growatt SPH BL-UP with GridZeno.

Growatt SPH BL-UP on the compatibility list, updated 31 October 2026.

• Live overview of solar, consumption and gridAll subscriptions
  Works
• Battery state of chargeAll subscriptions · requires a battery
  Works
• 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.
  Works
• Charge from the grid when power is cheapSmart and Pro · requires a battery
  Works
• Discharge the battery when power is expensivePro · requires a battery
  Works

Works: tested and measured on real hardware.

The dongle finds out by itself how your SPH is controlled and uses the way the inverter's firmware has.

Charge, hold and sell

With Growatt's VPP protocol when the firmware has VPP V2.01. Otherwise with the inverter's time windows: Battery First for charging and holding, Grid First for selling.

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.

Back afterwards

The dongle saves the inverter's own settings before it changes them the first time, and puts them back when the plan is done and after a restart.

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.

The type code 3501, 3502, 3503 or 3504 in holding 30000 (3501 is without VPP V2.01). The VPP version is in 30099, where 201 is V2.01.

With VPP V2.01

Growatt's VPP command: a power and a duration, which the dongle removes when the block ends. 30409 is a target, not a ceiling, so the dongle itself goes to 0 % when the battery reaches the block's target.

Without VPP V2.01

The inverter's time windows, as on the three-phase SPH. The inverter then reports no battery capacity, and the plan counts without a battery until the capacity comes from somewhere else.

What the dongle allows for

• If another system already has the VPP command on (30100 or 30407), GridZeno doesn't take it over and never releases it.
• A sale that stopped at its limit starts again only 2 percentage points above it, so the command isn't switched on and off with every point.

How it differs from its neighbours

• Growatt SPH: The three-phase SPH TL3 BH-UP has the type code 3601 and is always controlled with the time windows.

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.

Control

The VPP command in 30407-30410: 30408 is the duration, 30409 the power in per cent, 30410 = 1 when charging. 30100 = 1 turns it on. The dongle writes in the order 30408, 30409, 30410, 30100, 30407 and removes it with 30407 = 0, 30409 = 0, 30410 back and 30100 = 0.

Protocol

Holding 30099 shows the VPP version: 201 is V2.01.

Lowest charge level

608.

Export limit

123 in 0.1 %. 122 is the installer's switch and is never written.

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

Network cable with RJ45 plug. Approx. 20 minutes.

Port

485-1

Pin

A at pin 5 (RS485A), B at pin 1 (RS485B), GND at pin 2 (GND)

Where

In the port block on the underside between USB and BAT, behind the waterproof cover: CT1/METER1, CAN, 485-1 and the dry contact 1 2 3 at the top, DRM, NTC, 485-2 and VPP at the bottom. The cable is passed in through the cover's cable gland. 485-2 has the same pins, but is used for the battery if it speaks RS485.

See the full installation guide for Growatt SPH BL-UP

GridZeno Dongle for Growatt SPH BL-UP

This one works.

Growatt SPH BL-UP is the inverter GridZeno has been tested on. Check that your model is under SPH 3000, 3600, 4000, 4600, 5000 and 6000TL BL-UP, and that a battery is fitted if you want the battery controlled by the electricity price. If it still doesn't suit you, you have 100 days' free return.