Table of Contents
Compare Sungrow SG110CX and SG125CX-P2 against the proposed string layout, current limits, operating conditions and connection to the business. A larger number in the model name does not establish higher annual generation. A useful comparison identifies which parts of the project change when a different inverter is selected and what must be confirmed before purchase.
This article examines specific European versions using documentation available in October 2026. Both are grid-connected PV inverters. The comparison does not establish availability through ONG Solar, approval for a particular Ukrainian installation or the warranty terms of an individual supply.
Identify the exact versions
The SG110CX comparison uses SG110CX-V112, covered by the European datasheet version 1.1, dated 2022. For SG125CX-P2, the basis is datasheet V6, dated 2024, available from the model page covering Europe and other manufacturer-listed regions. Electrical parameters were also checked against the European section of user manual Ver19, October 2025.
SG110CX, SG110CX-P2 and models with other suffixes must not be treated as one product. A similar description in a quotation still needs the complete nameplate designation and matching documentation. The SG110CX-V112 figures below should not automatically be applied to every device marketed as SG110CX.
Prepare a selection record showing the model, hardware version, supply region, datasheet revision and required options. The Sungrow equipment page provides wider product context. Confirm the contents of an individual offer separately. Resolve an absent suffix or revision before comparing prices.
Put the specifications on a consistent basis
The table separates operating current from short-circuit current, and active power from apparent power. These distinctions are easily lost in short product summaries. All figures refer to the versions identified above.
| Parameter | SG110CX-V112 | SG125CX-P2 |
|---|---|---|
| Independent MPPTs | 9 | 12 |
| Strings per MPPT | 2 | 2 |
| Maximum input current per MPPT | 26 A | 30 A |
| Maximum short-circuit current per MPPT | 40 A | 40 A |
| MPPT operating voltage range | 200-1000 V | 180-1000 V |
| Maximum PV input voltage | 1100 V, subject to limits below | 1100 V, subject to limits below |
| Specified AC output | 110 kVA at 45 °C; 100 kVA at 50 °C | Rated active power 125 kW; maximum apparent power 125 kVA |
| Maximum AC output current | 158.8 A | 181.1 A |
| Maximum / European efficiency | 98.7% / 98.5% | 98.5% / 98.3% |
| Enclosure protection rating | IP66 | IP66 |
Datasheet efficiency is not a forecast of plant generation. Annual output depends on modules, temperature, string voltage, inverter loading, shading and operating restrictions. A small difference in maximum efficiency cannot establish the better economic choice for every roof.
Distinguish MPPTs, strings and current limits
An MPPT tracks the operating point of its connected group. Two strings sharing an MPPT do not receive two independent tracking algorithms. SG110CX-V112 has nine independent trackers; SG125CX-P2 has twelve. With two strings per tracker, that represents 18 and 24 supported string connections respectively, rather than 18 and 24 independent MPPTs.
Additional trackers can help when groups with different orientations or sunlight conditions need separate treatment. Determine the required count from the actual roof layout and electrical arrangement. A spare MPPT does not establish that an arbitrary short string or different module model can be added.
The 26 A and 30 A limits describe the combined operating input current on one MPPT for the respective versions. Each of two parallel strings cannot be assigned that entire allowance independently. The 40 A limit concerns a different quantity: permissible short-circuit current per tracker. It does not authorise a 40 A operating current.
The assessment needs the exact module model, operating current, short-circuit current and the conditions used to establish those values. Bifacial modules also require allowance for rear-side contribution. Module wattage cannot replace this check. Connector and individual input limits must be verified separately.
Read voltage limits with their conditions
A 1100 V maximum does not mean MPPT operation continues to 1100 V. Both compared versions have a 1000 V upper tracking limit. The SG110CX-V112 datasheet explicitly describes standby operation between 1000 and 1100 V. For SG125CX-P2, exceeding the MPPT operating range triggers inverter protection.
The lower tracking limit does not guarantee full output either. The European SG125CX-P2 manual section specifies 550-850 V for rated power, with additional requirements for configured string voltage and voltage differences between MPPTs. Its wider general range of 180-1000 V must not be interpreted as a promise of 125 kW at every point.
The designer checks open-circuit voltage at the project's low design temperature and operating voltage as modules heat up. The owner's deliverable should be an approved string schedule tied to the exact documentation. Comparing module counts alone, without temperature conditions, is insufficient.
Check AC output and thermal conditions
The selected SG110CX-V112 datasheet states output in kVA with temperature conditions. Do not rewrite it as an unconditional 110 kW at any temperature. SG125CX-P2 separately specifies 125 kW rated active power and 125 kVA maximum apparent power. Reactive power requirements and operating restrictions can affect the available active component.
The maximum AC currents also differ: 158.8 A and 181.1 A. Replacement requires checking the cable circuit, switchgear, protection and connection capacity. Installing a larger inverter does not automatically increase the site's agreed export allowance. Where export control is required, verify its implementation as part of the complete system.
A generation comparison needs the ambient temperature, ventilation and applicable power reduction conditions. An operating temperature limit does not guarantee rated output throughout the entire range. Assess the proposed installation location, particularly where equipment may be exposed to direct sunlight or nearby heat sources.
Check placement and protection equipment
Both versions have an IP66 enclosure rating, but this does not specify mounting clearances, support capacity or cooling space. Obtain the placement, service access and mounting requirements for the selected version. Cabinet dimensions are not the same as the area that must be reserved on site.
Include confirmed equipment weight, packaging and handling requirements in the logistics plan. SG125CX-P2 weight figures differ between document revisions, so an unqualified number should not be used to design supports or organise lifting. Obtain the final information before those works are agreed.
Verify the supplied protection configuration as well. The reviewed SG125CX-P2 documents list AFCI and DC Type I+II and AC Type II surge protection. For SG110CX, confirm the specific hardware version and options. Do not carry one variant's equipment list across the whole series or treat integrated features as a replacement for designing external protection.
Define the monitoring package
Both sets of documentation list RS485, with WLAN and Ethernet identified as options. A quotation mentioning monitoring should therefore identify the communication equipment, required functions and configuration work. Do not assume every network interface or additional device is already included in the base price.
Before acceptance, agree which information the owner will receive: inverter status, power, generation, messages and available string measurements. Site consumption and grid exchange require suitable metering arrangements. Inverter generation data alone cannot establish those flows.
The practical workflow for reading charts and preparing a support request is covered in the iSolarCloud monitoring guide. For this model comparison, the questions are communication-device compatibility, available functions and supply boundaries. After replacing an inverter, verify its identification and reporting in the monitoring system.
Compare two project scenarios
In a hypothetical new installation, a roof has several module groups experiencing different sunlight conditions. Twelve MPPTs and higher operating current per tracker may give SG125CX-P2 more options for distributing strings. That conclusion depends on voltage, current and the actual number of independent groups required. Additional inputs do not guarantee an energy gain by themselves.
In a second scenario, a business is considering replacing an existing SG110CX. Establish the reason for replacement and the condition of the existing arrangement first. If the problem is an export restriction, shading or a communication fault, higher nominal power may not resolve it. Existing string compatibility and permissible AC current also need checking.
For either scenario, compare the complete project change: inverter, supporting equipment, installation work, configuration and verification. The decision should explain the particular requirement that the alternative meets. The price difference between two enclosures does not reveal the full cost of changing the installation.
Request generation estimates for both configurations using the same weather data and explicitly identified differences. If module count, placement or export limits also change, the gain cannot be attributed solely to the inverter. For an operating plant, include interval records and the restriction log. This lets the team distinguish an equipment advantage from changed starting conditions and explain what produces the expected result.
Prepare a useful selection brief
Provide a package that allows both alternatives to be assessed:
- Complete inverter designations, hardware versions and documentation for the intended region.
- Module datasheets, roof plan, orientations and the existing or proposed string schedule.
- A single-line diagram, connection characteristics and agreed operating limits.
- Placement conditions, maintenance access and communication requirements.
- Required options, work, verification and acceptance documents.
Request separate confirmation of the supply's regional suitability, warranty terms and service process. European datasheet values do not replace verification for a particular site in Ukraine. Submit the information for solar plant design to establish the electrical arrangement and selection criteria. The result should be a justified configuration with clearly stated conditions of use.