SolaX X3 Ultra 20kW 3-Phase Hybrid Inverter | X3-ULT-20K

Description

The SolaX X3 Ultra 20kW (X3-ULT-20K) is a three-phase hybrid inverter for large homes and commercial and industrial solar-plus-storage. It combines the PV inverter, battery inverter and backup supply in one unit, with 20,000VA rated output (22,000VA maximum), 200% PV oversizing for arrays up to 40kWp, and two independent battery ports for lithium high-voltage storage.

On the PV side it has 2 MPP trackers with 2 strings each (4 strings), 36A per tracker, a wide 160 to 950V MPPT range, a low 200V start-up voltage and built-in shadow tracking. Maximum efficiency is 98.0% (97.7% European), and the 1000V maximum input suits long strings of high-power panels.

For backup and control it offers an EPS output of 20,000VA with 200% overload for 10 seconds, UPS-level switchover in under 10ms, microgrid and generator functions and parallel operation of up to 10 units. Smart load management for heat pumps and EV chargers responds within 0.3 seconds, and the IP66 enclosure with Type II SPD on AC and DC suits indoor or outdoor mounting.

20kW

Rated Output (22kVA Max)

40kWp

Max PV Array (200%)

36A

Per MPPT, 2 MPPTs

60A

Battery (2 x 30A)

<10ms

UPS-Level Switchover

IP66

Ingress Protection

Important Safety Information

Hybrid inverter, battery and backup (EPS) installations must be carried out by competent persons to BS 7671. At 29A per phase rated output this inverter is above the 16A per phase covered by G98, so the connection is normally agreed with the DNO under G99. EPS wiring changes the earthing and protection arrangements. Follow MCS requirements where relevant. PV strings up to 1000V DC and battery voltages up to 800V DC carry a serious shock and arc risk.

Check the Exact 20kW Model

SolaX makes three 20kW-class models. This page covers the X3-ULT-20K, which has 2 MPP trackers. The X3-ULT-20KP has 3 trackers, and the X3-ULT-19.9K is rated at 19,999VA. Confirm the model code on your order, and see the comparison table below.

Battery Compatibility

The X3-ULTRA works with SolaX high-voltage HS-series batteries and needs a minimum of 3 modules. If the total voltage of the 3 modules is below 127V and there is no PV input, the system will not start. Below 180V the inverter limits battery current to under 20A. Check the battery datasheet and manual for the number of modules and BMS units your design needs.

Metering for Export Control

SolaX states that a meter is needed for export control, and that three-phase on-grid inverters use a meter rather than a CT. SolaX's M3-40 guide lists the X3-ULTRA with its RS485 connection on RJ45 pins 4 and 5.

Dual Independent Battery Ports

Two independent battery ports of 30A each (60A total) let you expand storage easily, and the ports can be paralleled to connect one large battery.

High-Current PV Inputs

36A per MPPT and 45A short-circuit current suit high-power panels, with 200% oversizing for up to 40kWp on a 20kW inverter.

Robust Backup

UPS-level switchover under 10ms, 20,000VA EPS output, 200% overload for 10s, plus microgrid and generator functions.

Scalable Systems

Up to 10 units in parallel for both on-grid and off-grid operation when a site outgrows one inverter.

Smart Energy Management

Built-in shadow tracking and smart load management for heat pumps and EV chargers, with load response within 0.3 seconds.

Built to Last

IP66, Type II SPD on AC and DC, optional AFCI and an operating range of -35 to 60°C (derating above 45°C).

Model

Rated Output

MPPTs / Strings

Max PV Array

Net Weight

X3-ULT-20K (this product)

20,000VA

2 / 4

40kWp

46kg

X3-ULT-20KP

20,000VA

3 / 6

40kWp

47.5kg

X3-ULT-19.9K

19,999VA

2 / 4

40kWp

46kg

PV Input

Max. recommended PV array power

40,000Wp

Max. PV input voltage

1000V

Rated PV input voltage

600V

Operating voltage range

120 to 950V

MPPT voltage range

160 to 950V

Start-up voltage

200V

MPP trackers / strings per tracker

2 / (2 / 2)

Max. input current per MPPT

36A / 36A

Max. short-circuit current per MPPT

45A / 45A

AC Output (On-Grid)

Rated output apparent power

20,000VA

Max. output apparent power

22,000VA

Rated AC voltage

3W/N/PE, 220/380V or 230/400V

Rated output current

29.0A at 230V

Max. output continuous current

31.9A at 230V

Rated grid frequency

50 / 60Hz

AC frequency range

50 ± 5Hz / 60 ± 5Hz

Adjustable power factor range

1 (-0.8 to 0.8)

Battery

Battery type

Lithium

Battery voltage range

120 to 800V (full battery current from 180V)

Max. charge / discharge current

60A (30A x 2)

Battery ports

2 independent (BAT1 and BAT2)

Minimum battery

3 HS-series modules

EPS (Off-Grid) Output, With Battery

Rated EPS apparent power

20,000VA

Peak EPS output power

2 times rated power, 10s

Rated EPS voltage and frequency

230/400V, 50 / 60Hz

Switchover time

Under 10ms

Efficiency

Max. efficiency

98.0%

European efficiency

97.7%

General & Environment

Dimensions (W x H x D)

696 x 526 x 240mm

Net weight

46kg

Cooling

Smart air cooling

Ingress protection

IP66

Operating temperature range

-35 to 60°C (derating above 45°C)

Max. operating altitude

3,000m

Relative humidity

0 to 100% RH (condensing)

Overvoltage category

Mains: III, Battery: II, PV: II

Communication interfaces

RS485, CAN, DRM, DI/DO

Night-time power consumption

Below 5W

Topology

Non-isolated

Parallel operation

Up to 10 units, on-grid and off-grid

Protection & Standards

Surge protection (DC / AC)

Type II / Type II

Arc-fault circuit interrupter (AFCI)

Optional

Protections

Over/under voltage, DC isolation, DC reverse polarity, grid monitoring, DC injection monitoring, back-feed current monitoring, residual current detection, over-temperature, AC overcurrent, AC short-circuit, active anti-islanding

Certifications and standards

VDE 4105, G99, AS 4777, EN 50549, CEI 0-21, IEC 61727, PEA/MEA, NRS-097-2-1, RD1699, TOR

Which 20kW model is this?

The X3-ULT-20K: 2 MPP trackers with 2 strings each, 20,000VA rated output and 40kWp maximum PV. SolaX also makes the 20KP with 3 trackers and the 19.9K rated at 19,999VA, so check the model code when ordering.

How many strings and panels can I connect?

Four strings: 2 trackers with 2 strings each. Each tracker takes up to 36A within a 160 to 950V MPPT range, and the array can total up to 40kWp (200% of the 20kW rating). Have your installer check string voltages against the 1000V maximum.

Which batteries does it work with?

SolaX high-voltage HS-series batteries, with at least 3 modules. It has two independent battery ports of 30A each. SolaX's T-BAT-SYS-HV manual states that system is for residential applications only, so confirm the right battery for a commercial site with SolaX.

What backup power does it give?

An EPS output of 20,000VA with a peak of twice the rated power for 10 seconds and a switchover time under 10ms, which SolaX describes as UPS-level. Backup wiring changes earthing and protection, so it must be designed by a qualified electrician.

Do I need a meter?

Yes for export control. SolaX states a meter is needed for export control and that three-phase on-grid inverters work with a meter rather than a CT. SolaX's M3-40 guide lists the X3-ULTRA, connected over RS485.

Can it run with a generator or as a microgrid?

Yes. SolaX lists microgrid and generator functions. It also says that a string inverter connected to the hybrid inverter's EPS port can be powered from PV or battery energy during a grid outage.

Can I run several in parallel?

Yes, up to 10 units in parallel for both on-grid and off-grid systems, which suits sites that outgrow a single inverter.

Can it control a heat pump or EV charger?

Yes. SolaX lists smart load management for loads such as heat pumps and smart EV chargers, with a load response time within 0.3 seconds.

What is the warranty?

SolaX's warranty terms list the X3-ULTRA at 5 years standard, starting from installation (or shortly after production if earlier), with a free upgrade to 10 years when the inverter is connected to SolaXCloud and generation data has been uploaded. Terms vary by region and revision, so confirm the terms that apply to your purchase.

BTU Calculator

BTU & WATT Calculator

Room Dimensions

Length (in m):

Width (in m):

Height (in m):

Room Type

Living Room

Bedroom

Kitchen

Bathroom

Conservatory

Hallway

Glazing Type

Single Glazed

Double Glazed

Triple Glazed

External Walls

0 Wall

1 Wall

2 Walls

3 Walls

4 Walls

Insulation Level

Poor

Average

Good (New Build)

Calculate

Required Heating

0

Watts

0

BTUs