--- title: "Easun Power ISolar SMK 5K Off-grid Inverter: Specs & Datasheet | ComparePV" description: "Easun Power ISolar SMK 5K 5 kW off-grid inverter. Specs: 145 V max DC input, 13.5 kg." source: "https://comparepv.com/inverter/easun-power-isolar-smk-5k" updated: 2026-01-19 --- # Easun Power ISolar SMK 5K ## Identity - **Manufacturer:** Easun Power - **Model:** ISolar SMK 5K - **Series:** ISolar SMK - **Rated AC power:** 5 kW - **Type:** Off-grid - **Phases:** Single-phase - **Battery port:** yes ## How it compares Compared against 362 inverters from 3 to 6 kW. Ranks are within that class. | Measure | This inverter | Class median | Standing | Rank in class | | --- | --- | --- | --- | --- | | European efficiency | - | 97.2% | | | | MPPT trackers | - | 2 | | | | Max DC input voltage | 145 V | 600 V | Weak - bottom 2% | 311 | | Weight per kW | 2.7 | 3.3 | Typical | 119 | | Warranty | - | 5 yrs | | | ## Specification ### AC output - **Rated AC power:** 5 kW - **Max apparent power:** 5.00 kVA - **Phases:** Single-phase - **Nominal AC voltage:** 230 V - **Harmonic distortion (THD):** 3.0 % ### PV input - **Max DC input power:** 4.00 kW - **Max DC voltage:** 145 V - **MPPT voltage range:** up to 115 V ### Efficiency - **Max efficiency:** 93.0 % ### Battery - **Battery port:** Yes - **Grid-forming:** Yes ### Physical - **Dimensions:** 525 × 303 × 140 mm - **Weight:** 13.5 kg - **Operating temperature:** 0 to 55 °C - **Max humidity:** 95 % ### Connectivity and protection - **Interfaces:** Bluetooth, Display - **Protocols:** USB, RS232, RS485, Bluetooth, Dry-contact ### Pros - **Zero switching time (0 ms)** - A transfer time of 0 ms (true online UPS) effectively protects sensitive devices - servers, monitoring systems, and automation - from even the smallest power interruptions. Budget-friendly off-grid inverters (e.g., Voltronic Axpert) claim transfer times of 10-20 ms, which makes them unsuitable for protecting IT equipment. - **Parallel processing up to 9 units** - The SMK series supports parallel connection to up to 9 inverters, enabling power expansion, for example, to 45 kW (9 × 5 kW). This is a rare feature in the budget-friendly off-grid inverter segment, providing scalability for small commercial installations. - **Port BMS + Bluetooth as standard** - The integrated BMS port (RS485/CAN-BUS/RS232) enables direct communication with LiFePO₄ energy storage systems without the need for additional converters. Monitoring via Bluetooth and a mobile app is available without the need to purchase separate Wi-Fi modules, which reduces the overall installation cost. - **Pure sine wave, THD \<3% (for linear loads)** - The declared THD (Total Harmonic Distortion) below 3% for linear loads and below 8% for non-linear loads complies with the EN 62040-3 standard for VFI-SS-111 class inverters, as confirmed by the technical data published in the ENF Solar Datasheet. - **Peak power reserve of 2 × rated power** - The 5K model provides a peak power of 10,000 VA for 5 seconds, allowing for the start-up of electric motors (pumps, compressors) without overloading. A 2:1 (surge:nominal) ratio is the industry standard, but is particularly important for installations with inductive loads. ### Cons - **The product line has been discontinued.** - ISolar SMK is marked as discontinued. This means limited availability of spare parts, lack of firmware updates, and the risk of no longer receiving service support after the warranty period expires. For new installations, actively developed series (such as ISolar SMH III or newer) are recommended. - **One MPPT track** - The SMK series only has one MPPT input channel, which prevents connecting strings of panels with different orientations or tilt angles without performance losses. Competitive models in a comparable price range, such as the Deye SUN-5K-SG03LP1, offer 2 independent MPPT channels. - **90% efficiency in battery mode** - The inverter's efficiency in battery mode is declared at 90%, while more advanced premium-class units (such as Victron MultiPlus-II 5000 and SMA Sunny Island) achieve 95-96%. The difference of 5-6 percentage points translates into measurable losses during intensive off-grid operation. ## About this series The Easun Power ISolar SMK series are off-grid inverters with UPS functionality, designed to power homes or businesses using PV and batteries - even in locations where the grid is unstable or unavailable. A key feature is zero transfer time, which effectively protects sensitive equipment (such as servers, monitoring systems, and automation) from power interruptions. The built-in MPPT charge controller ensures optimal energy harvest from solar panels, with benefits particularly noticeable under variable weather conditions. In practice, the SMK series uses a single MPPT, simplifying configuration for installations with uniformly oriented modules. In terms of energy production efficiency, European efficiency is crucial - it demonstrates how the inverter performs under typical daily conditions, not just in an ideal test scenario. Monitoring is supported via Bluetooth and a mobile app, and communication with the system can be based on USB or RS232/RS485. Additionally, a BMS port is provided, facilitating integration with energy storage systems and battery operation monitoring. The series is primarily intended for residential and small commercial installations; it typically offers parallel operation and declared CE compliance, with warranty depending on the sales channel. ## Questions ### Does the Easun Power ISolar SMK inverter truly have a zero-switching time to battery power? Yes, the ISolar SMK series is designed with a UPS function, boasting a stated switching time of 0 ms. In practice, this means that when the mains power fails, devices such as servers, monitoring systems, and building automation systems do not experience any interruption in power supply. This is a key difference compared to typical off-grid inverters, which have switching times of 10-30 ms. ### What is the maximum power output that the ISolar SMK system can handle? This depends on the model. The 3K (24V) version can handle up to 1500W of PV power with an MPPT voltage range of 30-115 V DC and a charging current of up to 60A. The 5K (48V) version can handle up to 4000W of PV power with a voltage range of 60-115 V DC and a current of up to 80A. The maximum open-circuit voltage of the PV panels (Voc) cannot exceed 145 V DC in either version. ### Does the ISolar SMK system work with lithium-ion energy storage (LiFePO4) through a BMS port? The ISolar SMK series features a dedicated BMS communication port, which enables integration with LiFePO4 lithium batteries. This allows the inverter to monitor the battery's state of charge, temperature, and other parameters, and to adjust the charging profile to meet the battery's requirements. However, it is important to verify compatibility with a specific battery bank with the supplier, as BMS protocols can vary between manufacturers. ### How many ISolar SMK units can be connected in parallel within a single installation? The manufacturer declares the ability to connect up to 9 ISolar SMK units in parallel. This allows for scaling the off-grid system's power - for example, nine 5K units provide a total output of 45 kW. Parallel operation requires the use of appropriate communication cables and proper phase synchronization, so this type of configuration should be carried out by an experienced installer. ### What is the warranty on Easun Power ISolar SMK inverters? The standard manufacturer's warranty for the ISolar SMK series is 12 months. The actual scope and procedure for making a claim depend on the sales channel - local distributors may offer different service terms than purchasing directly from China. It is advisable to check where any repairs will be carried out and who will bear the cost of shipping the device to the service center before making a purchase. ### Is the Easun Power ISolar SMK series still available for sale? The ISolar SMK series has been discontinued by Easun Power and is no longer actively distributed as a new product. You may occasionally find examples in the warehouses of distributors or on the secondary market. For those seeking similar features (off-grid, UPS 0 ms, MPPT, BMS), the manufacturer recommends newer series from the current product range, such as the ISolar SMG II or other active series of Easun Power inverters. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/inverters/ISolar-SMK-5K-Brochure-f2f9f286912f.pdf) ## Alternatives | Inverter | Rated AC | Euro efficiency | MPPT | Weight | Difference | | --- | --- | --- | --- | --- | --- | | [Growatt SPF 5000 ES](https://comparepv.com/inverter/growatt-spf-5000-es) | 5 kW | | 1 | 12.0 kg | 1.5 kg lighter | | [Growatt SPF 5000T DVM](https://comparepv.com/inverter/growatt-spf-5000t-dvm) | 5 kW | | | 47.0 kg | 33.5 kg heavier | | [Growatt SPF 5000T DVM-MPV](https://comparepv.com/inverter/growatt-spf-5000t-dvm-mpv) | 5 kW | | | 47.0 kg | 33.5 kg heavier | | [Growatt SPF 3500 ES Lite](https://comparepv.com/inverter/growatt-spf-3500-es-lite) | 5 kW | | 1 | 9.2 kg | 4.3 kg lighter | | [Growatt SPF 5000 ES Lite](https://comparepv.com/inverter/growatt-spf-5000-es-lite) | 5 kW | | 1 | 9.8 kg | 3.7 kg lighter | | [Growatt SPF 5000TL HVM](https://comparepv.com/inverter/growatt-spf-5000tl-hvm) | 5 kW | | | 11.5 kg | 2.0 kg lighter | | [Ginlong Solis S6-EO1P5K-48](https://comparepv.com/inverter/ginlong-solis-s6-eo1p5k-48) | 5 kW | | 1 | 13.8 kg | Similar on paper | | [Easun Power SMP-5KW](https://comparepv.com/inverter/easun-power-smp-5kw) | 5 kW | | | 12.0 kg | 1.5 kg lighter | --- Source: https://comparepv.com/inverter/easun-power-isolar-smk-5k