Dimmer Per Circuit Capacity 20A Fixture Calculator

Reconcile actual fixture patch/RMS-current ledger by caller circuit usable budgets, not assuming every circuit is 20A, certified derating, inrush or electrical installation clearance.

Description

Circuit-current ledgers compare recorded RMS fixture loads with explicit usable budgets.

Circuit-current ledgers compare recorded RMS fixture loads with explicit usable budgets. A circuit label does not imply a 20 A allowance.^[1]

Enter aligned nonempty nonnegative currents/zero-based integer assignments and 1–128 nonnegative circuit limits. Return loads, signed margins and strict-overbudget indices.

When to use Dimmer Per Circuit Capacity 20A Fixture Calculator

Use Dimmer Per Circuit Capacity 20A Fixture Calculator when you need to evaluate the supplied records under the calculation and evidence rules below. No derating, inrush, breaker performance or electrical installation approval is assessed.

Prepare the actual venue, production, inventory or financial records requested. Confirm units and supply applicable local limits or verified catalog values.

How to use Dimmer Per Circuit Capacity 20A Fixture Calculator and understand its results

Prepare the actual venue, production, inventory or financial records requested. Confirm units and supply applicable local limits or verified catalog values.
Enter fixtureMeasuredCurrentArms, assignedCircuitNumbers, callerCircuitUsableCurrentLimitsA using the field table and calculation rules, then run the tool.
Read observedLoadsByCircuitA, signedCircuitCurrentMarginsA, overCallerCircuitBudgetIndices. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
fixtureMeasuredCurrentArms	Fixture measured current arms	list of number	Required
assignedCircuitNumbers	Assigned circuit numbers	list of number	Required
callerCircuitUsableCurrentLimitsA	Caller circuit usable current limits a	list of number	Required

Enter aligned nonempty nonnegative currents/zero-based integer assignments and 1–128 nonnegative circuit limits. Return loads, signed margins and strict-overbudget indices.

load[circuit]=sum(assigned currents); margin=limit−load

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
observedLoadsByCircuitA	Observed loads by circuit a	list of number
signedCircuitCurrentMarginsA	Signed circuit current margins a	list of number
overCallerCircuitBudgetIndices	Over caller circuit budget indices	list of number

json

{
  "input": {
    "fixtureMeasuredCurrentArms": [
      3,
      4,
      5
    ],
    "assignedCircuitNumbers": [
      0,
      0,
      1
    ],
    "callerCircuitUsableCurrentLimitsA": [
      6,
      10
    ]
  },
  "output": {
    "observedLoadsByCircuitA": [
      7,
      5
    ],
    "signedCircuitCurrentMarginsA": [
      -1,
      5
    ],
    "overCallerCircuitBudgetIndices": [
      0
    ]
  }
}

Limitations and assumptions

No derating, inrush, breaker performance or electrical installation approval is assessed.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Practical Prop Lamp Wattage Circuit Load Add Calculator: Single-phase RMS current depends on true power, supply voltage and matched power factor. Installed but inactive lamps remain separate. For a complementary task, use DMX Universe Channel Address Planner Tool: DMX patch planning assigns contiguous fixture footprints within 512-channel universes. A fixture cannot span a universe boundary in this model.

References

Dimmer Per Circuit Capacity 20A Fixture Calculator — tool.io

Similar or alternative tools

Practical Prop Lamp Wattage Circuit Load Add Calculator
Single-phase RMS current depends on true power, supply voltage and matched power factor. Installed but inactive lamps remain separate.
DMX Universe Channel Address Planner Tool
DMX patch planning assigns contiguous fixture footprints within 512-channel universes. A fixture cannot span a universe boundary in this model.