Free tool · OmniSol Global

PV System Configurator

Enter capacity + module/inverter datasheet values → get string sizing, inverter count, cable cross-section, protection ratings and an indicative FOB budget. Accuracy ±20–40%. Not a formal quotation.

1Tell us your project

Capacity, roof type, site temperature and cable run.

2Use equipment presets

Default module and inverter values are ready to calculate.

3Review the quote signals

Modules, strings, inverters, containers and FOB range.

Project Parameters

10–50,000 kW

Affects mounting cost

Default works for budgetary sizing

Pick the closest string inverter

Use lowest recorded / design temp

String → inverter, one way

These are standard wind-zone baseline values. High-wind / cyclone sites may require 50–100% more mounting material. Use the wind load calculator for site-specific support spacing.

Optional roof sketch

Draw your roof on satellite imagery for an instant area check

Search an address, trace one or more roof surfaces, then compare usable roof area with the target DC capacity before requesting a quote.

Module datasheet detailsOpen only if the preset differs

300–800 W

Open-circuit voltage

Must be < Voc

Short-circuit current

Must be < Isc

Typically −0.24 to −0.30

Module dimensions

15–45 kg

Always verify with the official datasheet — values vary by manufacturer even at the same rated power.

Inverter datasheet detailsMPPT voltage and string inputs

Startup threshold

Per inverter

Advanced optionsDC/AC ratio · voltage drop · layout

Typical: 1.1–1.3

Required in AU (AS/NZS 5033) and some EU markets

Calculated default: 26 | valid range: 5–28

Configuration Results

Auto-updates

Modules

858

590W panels · 506.2 kW DC

Strings

33

26 panels per string

Inverters

2×250kW

DC/AC 1.01

Containers FOB

~2

40HQ estimate

Ready for a budgetary quote

Target 500 kW gives 506.2 kW actual DC. Draw the roof to check whether the capacity physically fits.

String Layout

INV-1 · 250kW
17 strings
INV-2 · 250kW
16 strings

Each string uses 26 modules. Total strings: 33.

Budget Mix

FOB range$110,000 – $141,000
Modules54%
Inverters9%
Mounting21%
BOS17%

Preliminary FOB range (-10% / +15%)

$110,000 – $141,000

≈ $0.218–$0.278/W FOB China

This band applies to standard grid-tied C&I (commercial rooftop) BOMs only. Off-grid, hybrid and storage-inclusive systems are priced on a different basis and quoted separately.

Container Plan - ~2 × 40HQ

40HQ #1 · 689 modules + rails

40HQ #2+ · 169 modules + mounting + BOS

Estimated mounting weight: 5,541 kg. Final loading depends on packing list.

Technical detailsOpen for Voc, cable, protection devices

String Design

Voc at T_min (corrected)
52.98 V

52.6V × temp factor

System voltage limit
1500 V
Max modules/string (N_max)
28
Min modules/string (N_min)
5

MPPT start threshold

Modules/string (default)
26

N_max - 2 = 26, clamped to [5, 28]

Array Configuration

Actual DC capacity
506.2 kW

+1.2% vs target

Total modules
858
Total strings
33

Inverters

Inverter count
2 × 250 kW
Strings per inverter
17 (last: 16)
DC/AC ratio (actual)
1.01
DC/AC ratio 1.01: configuration is well-balanced.

DC Cable

Required cross-section
≥ 2.04 mm²
Selected standard size
4 mm²
Estimated total length
~3,300 m

Rough estimate only

Protection Devices

String fuse
25 A

Isc × 1.5 = 20.8 A

DC main breaker / inverter
400 A

17 str × Imp × 1.25

SPD units
5

DC/AC per inverter + main panel

Refine mounting with the Wind Load Calculator →See the full PV system kit →

Price basis: 2026-06 China FOB. Module prices fluctuate weekly. Formal quotes valid 7-14 days only.

Scope & Limitations — Please Read

  1. Mounting is estimated at standard wind-zone baseline. Actual quantity depends on site wind/snow load. High-wind and cyclone sites may require 50–100% more material. Use the wind load calculator (AS/NZS 1170.2 / ASCE 7-22 / EN 1991-1-4) for accurate support spacing and mounting BOM.
  2. Electrical BOS uses typical-layout estimates. Actual cable quantity depends on inverter placement, roof plan and routing path. A roof layout sketch is required for a precise quote.
  3. Module and inverter parameters must come from the official datasheet. Voc/Vmp values differ across manufacturers even at the same rated wattage and directly change string design.
  4. Price assumptions are based on 2026-06 China FOB market. Module prices have fluctuated weekly since April 2026 (export tax change). Formal quotes are valid for 7–14 days only.
  5. This tool covers DC side to inverter AC output. Main switchboard, metering, grid connection approval (SP/EMA Singapore, NEM Malaysia, AS/NZS 4777 Australia, etc.) are the EPC's scope.
  6. Energy storage is not included. Specify storage requirements separately when requesting a quote.
  7. All pricing is FOB China port (Ningbo / Xiamen). Ocean freight, destination port charges, import duties and installation are excluded.
  8. Roof areas drawn on satellite imagery are indicative only. Imagery may be outdated; obstructions, shading, structural capacity, fire setbacks and local code clearances are not assessed. A site survey or roof drawing is required before final layout design. Drawn shapes are submitted only with your quote request and are not stored otherwise.

Engineering Reference

How This Configurator Works

How to use this tool

Enter four groups of inputs — module datasheet parameters, inverter datasheet parameters, project capacity and site conditions. The tool applies the electrical design equations used by PV engineers and returns a preliminary BOM and indicative FOB budget. It is not a certified design document.

How many solar panels per string?

The upper bound is the system voltage (1000V or 1500V) divided by the temperature-corrected Voc at the site minimum temperature. The lower bound ensures the string voltage exceeds the inverter MPPT minimum. Formula: Voc_corrected = Voc × (1 + TempCoeff/100 × (T_min − 25)). The tool defaults to two below the upper limit to leave engineering headroom.

N_max = floor(V_sys / Voc_corrected)

How is inverter count calculated?

Inverter count is the higher of two constraints: (1) total strings ÷ max string inputs per inverter; (2) DC array capacity ÷ (inverter AC rating × target DC/AC ratio). For a 506 kW array targeting DC/AC 1.2 with 250 kW inverters: need at least ceil(506 / (250 × 1.2)) = 2 inverters. The tool picks the more conservative value.

What DC cable cross-section is required?

Cable is sized to keep voltage drop within the allowed limit (typically 1%). Result is rounded up to the nearest standard size: 4, 6, 10, 16 or 25 mm². Runs under ~80 m typically need only 4 mm²; beyond ~90–100 m, step up to 6 mm².

A = (2 × L × Imp) / (56 × ΔV)

How are protection device ratings chosen?

String fuse: Isc × 1.5, rounded to next standard size (15, 20, 25, 32, 40 A). DC main breaker per inverter: strings-per-inverter × Imp × 1.25, rounded to next standard breaker (125–630 A). SPD count: two per inverter (DC and AC sides) plus one for the main panel.

What does the budget range mean?

A −10% / +15% band is applied around the modelled budget to reflect lot-pricing variation, BOS layout efficiency and market movement. The range uses current China FOB rates. This is not a quotation — formal quotes require module brand, inverter model, roof layout and delivery date.

How many 40HQ containers does a solar project need?

Container count is the higher of: (1) modules only — total modules ÷ modules per 40HQ (22,000 kg ÷ module weight); (2) total cargo — (modules + mounting) × 1.05 buffer ÷ 22,000 kg. For 858 × 590W modules at 31.9 kg each, about 689 fit per 40HQ → minimum 2 containers.