String Sizing & Battery Calculator
Run a preliminary voltage, current and battery screen for stored module and Qbits inverter data, then verify current documents and engineering requirements.
Solar String and Battery Sizing Calculator
Pick a module and a Qbits inverter, enter the module count and your site's module temperatures, and see how the modules could be split into strings across the MPPTs. It is a first screen: check the result against the module and inverter datasheets and your site conditions before you design or buy.
System Inputs
Use module temperatures, not just ambient air temperatures. Cold raises Voc; heat lowers Vmp. The defaults are illustrative and must be replaced for your site.
PV string sizing uses the hybrid inverter selected above; the battery bank is sized from the backup loads below.
Battery sizing uses your DOD and conversion-efficiency assumptions, then rounds to illustrative 5 kWh units. These are not approved battery packs or a compatibility recommendation.
Preliminary Configuration
Your optimal string layout will appear here
Pick a panel & inverter, then hit Calculate.
Preliminary calculation using stored data. Verify current model documents, site assumptions and approval requirements.
Uses stored module and inverter data · Temperature-corrected voltage window, per-MPPT current & DC/AC ratio checks.
Indicative sizing tool — always confirm against the manufacturer datasheet before installation.
How to use this solar string calculator
Select the exact panel and inverter, enter the module count and project-specific module temperatures, then review each MPPT separately. Cold-corrected open-circuit voltage must stay within all applicable equipment limits; hot operating voltage must remain in the tracking window.
For an illustrative module with 50 V Voc and a −0.25%/°C coefficient at −5°C, corrected Voc is 53.75 V. Ten modules in series give 537.5 V. Compare that with the inverter, module and other equipment limits before adding design margins. This example is not a model recommendation.
What it calculates
For the module and inverter you pick, the tool works out a string size, how many strings and modules go on each MPPT, the voltage window across your temperature range, the per-MPPT current against the stored limit, and the DC/AC ratio with an illustrative peak-clipping comparison. For hybrid systems it also estimates battery energy from your backup loads, in illustrative 5 kWh units. You can download the inputs and results as a JSON file.
What you enter
System type (on-grid or hybrid), one of the stored modules (Adani, Vikram Solar and Waaree, 550 W to 715 W), a Qbits inverter, the number of modules, and the minimum and maximum module temperature. Hybrid mode adds backup loads, depth of discharge, backup days and a battery-to-load efficiency assumption. The default temperatures are illustrations and should be replaced with your site's values.
What the result does and does not check
This is a preliminary voltage and current screen. The stored catalogue values require verification against the supplied model revision. Short-circuit current is conservatively screened against the stored operating-current limit because separate certified Isc limits are not available in this dataset. A result is not a complete electrical design or approval.
Verify maximum permitted PV power, module system-voltage limits, bifacial current uplift, design factors, cable and fuse ratings, protection, startup/full-power tracking requirements, battery discharge power and local utility rules separately. Peak clipping is an illustrative power comparison, not an annual energy forecast. The battery estimate sizes energy only; it does not compare your load power with the inverter's off-grid rating or battery current limits.
Check the result against the documents
Open the Qbits inverter datasheets for the exact model and compare MPPT voltage window, current limits and MPPT count. Browse on-grid inverters or hybrid inverters to compare families, and see the datasheet guide and battery-sizing worksheet. After you calculate, the result panel links the matching model page and datasheet, and you can send the equipment documents and layout to Qbits for a technical review.