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Lighting Group Circuit Planner

Allocate indivisible lighting groups to proposed circuits using actual input VA and continuous-load weighting; show a feasible plan or oversized groups.

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Inputs that matter
Fixture and circuit design basis, Circuit voltage (V), Proposed circuit rating (A), Indivisible fixture groups, and 1 more
Output to expect
Lighting group circuit allocation
  • Check the units and required inputs before comparing results.
  • Keep the assumptions with a copied result so you can reproduce the calculation later.
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Reference & details

How it works

Lighting group circuit allocation

Allocate indivisible lighting groups to identical proposed circuits using actual fixture input VA and the ordinary 125% continuous-load allowance. Each row stays on one circuit. The deterministic first-fit-decreasing arrangement is a feasible arithmetic plan when all groups fit; it is not guaranteed to use the fewest circuits.

Group weighted VA = quantity × fixture VA × (1.25 if continuous, otherwise 1); circuit weighted VA capacity = voltage × breaker A.

Updated: September 2026

Example Scenarios

Try the built-in example, then replace its source data with your actual documented values. Retain failed comparisons and unresolved decisions.

→ 1 circuits in a feasible group allocation

FAQ

Allocate indivisible lighting groups to identical proposed circuits using actual fixture input VA and the ordinary 125% continuous-load allowance. Each row stays on one circuit. The deterministic first-fit-decreasing arrangement is a feasible arithmetic plan when all groups fit; it is not guaranteed to use the fewest circuits.

Use the exact equipment, dimensions, current ratings, operating conditions and applicable requirements described in the selected mode. Unknown values are not replaced by a generic wire, device count or capacity. Illustrative examples are arithmetic examples, not an approved installation.

Save planning case keeps an explicit local history entry. Copy MD retains current inputs, source notes and interpretation; Download CSV exports the current result breakdown. Export a separate copy before changing devices or clearing browser storage.

About Lighting Group Circuit Planner

Allocate indivisible lighting groups to identical proposed circuits using actual fixture input VA and the ordinary 125% continuous-load allowance. Each row stays on one circuit. The deterministic first-fit-decreasing arrangement is a feasible arithmetic plan when all groups fit; it is not guaranteed to use the fewest circuits.