Solar inverters · Compare

Fronius Primo GEN24 4.0 vs SolaX X3-IES-4K

AC power: Fronius Primo GEN24 4.0 4 kW, SolaX X3-IES-4K 4 kW. The SolaX X3-IES-4K is better on 4 of 10 comparable points.

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Both models in detail

Who wins where

  • Fronius Primo GEN24 4.0
  • SolaX X3-IES-4K
PerformanceEfficiencyElectricalConnectivity & smartDimensions & weight
Performance: Fronius Primo GEN24 4.0 34, SolaX X3-IES-4K 41; Efficiency: Fronius Primo GEN24 4.0 36, SolaX X3-IES-4K 75; Electrical: Fronius Primo GEN24 4.0 35, SolaX X3-IES-4K 69; Connectivity & smart: Fronius Primo GEN24 4.0 37, SolaX X3-IES-4K 37; Dimensions & weight: Fronius Primo GEN24 4.0 77, SolaX X3-IES-4K 9

Biggest differences

FactPrimo GEN24 4.0X3-IES-4K
Weight15.4 kg35 kg
MPPT voltage min.210 V110 V
MPPT voltage max.530 V950 V
Max. PV array power6 kWp8 kWp
Max. input current per MPPT22 A20 A
All specifications ↓

Score per area = position (0–100) relative to all 263 models in this category; higher is better.

Technical specificationsFroniusPrimo GEN24 4.0SolaXX3-IES-4K
Performance
AC power4 kW14 kW1
Max. PV array power6 kWp28 kWp✓3
MPP trackers2223
Efficiency
Max. efficiency97.6 %2–
European efficiency97.1 %297.7 %✓3
Noise
Noise42 dB(A)2–
Electrical
MPPT voltage min.210 V2110 V✓3
MPPT voltage max.530 V2950 V✓3
Max. input current per MPPT22 A✓220 A3
Phases1131
Connectivity & smart
Hybrid (battery-ready)No1No1
Backup powerYes2Yes3
Wi-Fi / monitoringYes2–
Dimensions & weight
IP ratingIP662IP663
Width474 mm2717 mm3
Height530 mm2405 mm3
Depth165 mm2209.5 mm3
Weight15.4 kg✓235 kg3

Frequently asked questions

Which is better: the Fronius Primo GEN24 4.0 or the SolaX X3-IES-4K?

AC power: Fronius Primo GEN24 4.0 4 kW, SolaX X3-IES-4K 4 kW. The SolaX X3-IES-4K is better on 4 of 10 comparable points.

What is the AC power of the Fronius Primo GEN24 4.0 and the SolaX X3-IES-4K?

Fronius Primo GEN24 4.0: 4 kW. SolaX X3-IES-4K: 4 kW.

Which is better on weight: the Fronius Primo GEN24 4.0 or the SolaX X3-IES-4K?

Fronius Primo GEN24 4.0: 15.4 kg. SolaX X3-IES-4K: 35 kg.

Which is better on MPPT voltage min.: the Fronius Primo GEN24 4.0 or the SolaX X3-IES-4K?

SolaX X3-IES-4K: 110 V. Fronius Primo GEN24 4.0: 210 V.

How we collect and check this data →

Sources

  1. ENA Type Test Register (inverters) — Energy Networks Association (ENA) · accessed 27 Sept 2026
  2. Fronius Primo GEN24 & GEN24 Plus 3.0 - 6.0 kW – datasheet, EN V04 (June 2025) — Fronius International GmbH · accessed 27 Sept 2026
  3. X3-IES Series All-in-one Residential ESS Datasheet, V1.8 — SolaX Power · accessed 17 Oct 2026