Should I enter Imp or Isc?

Enter both from the module datasheet. The calculator reports adjusted operating current and adjusted short-circuit current separately.

Does the adjustment factor come from the calculator?

No. The factor is entered by the user from the project method, product source or competent review basis.

What if no current limit is known?

Enter 0 only when no limit is being compared. The current row can still feed the PV DC cable worksheet.

Can this select a fuse or isolator?

No. It records current arithmetic only. Product ratings, protection and installation requirements remain external.

Why is Isc checked against Imp?

The calculator requires Isc to be at or above Imp because module short-circuit current should not be lower than operating current in this worksheet.

PV string current calculator

Imp_adj = Imp x F; Isc_adj = Isc x F; Iarray = Isc_adj x Nparallel; Margin = Ilimit - Iarray

Enter module Imp and Isc from the exact module datasheet.
The current adjustment factor is entered by the user from the source method.
Entered current limit is optional and only a comparison value.
The worksheet does not select fuses, isolators or cable sizes.

Formula variables
Variable	Meaning	Unit	Use
Imp	Module operating current	A	Entered module Imp from the datasheet.
Isc	Module short-circuit current	A	Entered module Isc from the datasheet.
F	Current adjustment factor	factor	User-entered multiplier for the current record.
Imp_adj	Adjusted string Imp	A	Module Imp multiplied by the entered factor.
Isc_adj	Adjusted string Isc	A	Module Isc multiplied by the entered factor.
Nparallel	Parallel strings	strings	Number of parallel strings in the array current record.
Iarray	Array short-circuit current	A	Adjusted string Isc multiplied by parallel strings.
Ilimit	Entered current limit	A	Optional user-entered product or source comparison value.
Margin	Current margin	A	Entered current limit minus adjusted array short-circuit current.

PV string current calculator technical guide

Estimate PV string and array current from module Imp, module Isc, parallel strings and an entered adjustment factor for Australian solar project records.

Use this page when PV module current data needs to become a string or array current record before cable, isolator, protection or inverter-input review. It keeps the current arithmetic visible without pretending to choose equipment.

PV Current Boundary

This calculator does not select fuses, isolators, DC cables, inverter inputs or product ratings. It only multiplies entered module current values by an entered factor and the number of parallel strings.

What the current row feeds
Downstream task	Current value usually needed	Where to go next
PV DC cable voltage drop	Array current	PV DC cable voltage-drop calculator.
Product current comparison	Adjusted Isc and entered limit	Product documentation and competent review.
String voltage	Module voltage, count and temperature	PV string voltage calculator.
Protection selection	Fault current, product ratings and installation method	Outside this worksheet.

Data Checklist

PV current inputs
Value	Where it normally comes from	Stop if
Module Imp	Exact module datasheet	The module model or revision is unknown.
Module Isc	Exact module datasheet	Isc is entered below Imp.
Parallel strings	Array layout or inverter input schedule	The strings do not share the same current path.
Adjustment factor	Project method, product source or competent review	The factor source is not recorded.
Current limit	Product documentation or source record	The limit is copied from the wrong input or product.

Review Workflow

Identify the current reference from the array layout, inverter input schedule or string table.
Enter module Imp and Isc from the exact module datasheet.
Enter parallel string count for the current path being reviewed.
Enter the adjustment factor supplied by the project source method.
Enter a current limit only when a source value is being compared.
Read adjusted string current and adjusted array short-circuit current separately.
If the margin is negative, review string count, factor, product limit and source basis before carrying the record forward.

Worked Records

PV current examples
Situation	Inputs	Result	Record use
Two-string record	Imp 13.2 A, Isc 14.1 A, 2 strings, factor 1.25, 40 A limit	Array short-circuit current 35.25 A	Below the entered limit and ready for cable worksheet handoff.
Three-string review	Same module current, 3 strings, factor 1.25	Array short-circuit current about 52.88 A	Above the entered 40 A limit; stop for review.
Single-string row	Imp 12.8 A, Isc 13.6 A, 1 string, factor 1.2	Current row supports downstream records	Keep product-current and cable tasks separate.

Stop Points

Module current values are copied from the wrong datasheet.
The entered factor is not sourced.
Parallel string count is not tied to the actual current path.
The entered current limit is below the adjusted array current.
The result is being treated as a fuse, isolator or cable selection.

Module Imp: 13.2 A
Module Isc: 14.1 A
Parallel strings: 2
Adjustment factor: 1.25

Adjusted string Imp16.5 A
Adjusted string Isc17.63 A
Array short-circuit current35.25 A

Array short-circuit current35.25 A

Current margin against the entered limit is 4.75 A.

The adjusted array short-circuit current remains below the entered current limit.

Module current values are entered from the module datasheet.
The adjustment factor is entered by the user.
Protection and product selection remain separate checks.

Module Imp: 13.2 A
Module Isc: 14.1 A
Parallel strings: 3
Adjustment factor: 1.25

Adjusted string Imp16.5 A
Adjusted string Isc17.63 A
Array short-circuit current52.88 A

Array short-circuit current52.88 A

Current margin against the entered limit is -12.88 A.

The adjusted short-circuit current exceeds the entered limit and should trigger product review.

Parallel string count is entered as a whole number.
The current limit is a source record, not selected by the calculator.
The worksheet does not choose fuses or isolators.

Module Imp: 12.8 A
Module Isc: 13.6 A
Parallel strings: 1
Adjustment factor: 1.2

Adjusted string Imp15.36 A
Adjusted string Isc16.32 A
Array short-circuit current16.32 A

Array short-circuit current16.32 A

Current margin against the entered limit is 8.68 A.

The row creates a traceable current input for downstream cable and product records.

The module Isc is not below module Imp.
No controlled standards table values are embedded.
Manufacturer documentation remains controlling.