Circuit load grouping calculator
Group entered circuit load rows by Australian switchboard schedule labels and phase records.
Irow = Iload x Qty; GroupTotal = sum(Irow by group label); PhaseTotal = sum(Irow by phase); LargestGroup = max(GroupTotal)- Circuit current and quantity are user-entered.
- Group labels are exact schedule labels.
- Phase totals are preparation values.
- Demand factors and phase balancing stay in separate calculators.
| Variable | Meaning | Unit | Use |
|---|---|---|---|
| Iload | Circuit load current | A | Entered current per circuit row. |
| Qty | Circuit row quantity | qty | Entered row count. |
| Irow | Row load | A | Circuit current multiplied by quantity. |
| GroupTotal | Grouped load | A | Sum of row loads sharing the same group label. |
| PhaseTotal | Phase load summary | A | Sum of row loads sharing the same phase label. |
| LargestGroup | Largest grouped load | A | Highest group total compared with the entered review limit. |
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Circuit load grouping calculator technical guide
Group entered circuit rows by schedule label and phase for Australian load schedule preparation.
Use this calculator when a circuit list needs to be sorted into load groups before demand factors, phase balancing or switchboard capacity checks. It keeps each entered row visible while producing group totals and phase totals from the same source record.
Field Use Cases
| Work setting | Real question | Useful action from this page |
|---|---|---|
| Tenancy fit-out | Which entered rows belong to lighting, small power or mechanical groups? | Group rows by the project schedule label. |
| Switchboard schedule | Which group is the largest before demand factors are applied? | Compare the largest group with the entered review limit. |
| Phase preparation | What phase totals follow from the same circuit list? | Carry L1, L2 and L3 totals into a phase worksheet. |
| Estimating handoff | Which rows need clearer labels before costing or demand work? | Keep ungrouped or fallback labels visible. |
| Design review | Is a single group dominating the row list? | Read the largest group load and source rows. |
This worksheet is useful before maximum demand because it separates record keeping from demand assumptions. The calculator does not choose demand factors and does not decide where circuits should be connected.
Data checklist
| Value | Where it normally comes from | Stop if |
|---|---|---|
| Circuit reference | Load schedule, drawing tag or board schedule | The row cannot be traced to the project record. |
| Group label | Schedule grouping such as lighting, small power or mechanical | The label is being invented after the calculation. |
| Phase label | Recorded phase from the schedule or measured record | Phase labels are missing or uncertain. |
| Load current | Equipment list, circuit schedule or measured current record | Different rows use incompatible current bases. |
| Quantity | Circuit count, equipment count or repeated row count | Quantity is used to hide separate rows that should stay visible. |
The worksheet works best when each row has a clear label, group and phase. If a row is uncertain, keep it visible rather than folding it silently into another group.
Review Workflow
| Step | Record to check | Move to |
|---|---|---|
| Confirm row list | Circuit schedule or equipment list | Enter circuit references. |
| Assign group labels | Project load groups | Read group totals. |
| Confirm phase labels | Board schedule or measured record | Read phase totals. |
| Check largest group | User-entered review limit | Decide which group needs closer source review. |
| Continue the task | Demand factors, maximum demand or phase balancing | Use the calculator that owns that next question. |
The review path is deliberately narrow. It helps the row list become clean enough for later calculations without turning this page into a demand or board-capacity decision.
Worked grouping record
A fit-out schedule enters six 8 A lighting rows, three 16 A small-power rows, two 24 A mechanical rows and one additional 18 A mechanical row. The review limit is 55 A.
The connected row load is 162 A. Lighting totals 48 A, small power totals 48 A and mechanical totals 66 A. The mechanical group is the largest and is above the entered review limit.
| Value | Result |
|---|---|
| Total connected load | 162 A |
| Lighting group | 48 A |
| Small power group | 48 A |
| Mechanical group | 66 A |
| L1 phase total | 66 A |
| L2 phase total | 48 A |
| L3 phase total | 48 A |
The result gives a clear source record for the next worksheet. If the mechanical group needs a different demand basis, that decision belongs in the demand factor or maximum demand workflow.
Method boundary
| Method element | What this page does | What remains outside |
|---|---|---|
| Row load | Multiplies entered current by entered quantity. | Confirming equipment ratings or measured current source. |
| Group total | Adds row loads that share the same group label. | Choosing demand factors for that group. |
| Phase total | Adds row loads that share the same phase label. | Phase balancing, circuit movement or board arrangement. |
| Largest group | Finds the highest group total and compares it with the entered limit. | Deciding whether the group is acceptable for a project. |
Keeping the method narrow makes the output easier to reuse. The page creates a grouped record, not a complete demand calculation.
Stop points
- The circuit list has no schedule or drawing reference.
- Group labels do not match the project record.
- Some rows use connected load while other rows use measured demand.
- Phase labels are unknown or copied from an older schedule.
- The grouped result is being treated as a final board decision.
- Demand factors, diversity factors, phase balancing or spare capacity are now the real question.
When a stop point appears, keep the row list as a preparation record and resolve the source values before carrying the grouped totals downstream.
Fit-out circuit grouping
A tenancy schedule groups lighting, socket outlet and mechanical circuit rows before a demand worksheet is prepared.
- Schedule reference
- CLG-1
- Circuit rows
- 4
- Group limit
- 55 A
- Total row load162 A
- Largest groupMechanical at 66 A
Use the status to decide which grouped rows need closer schedule review.
The mechanical group is the largest group and is above the entered review limit, so its source rows should stay visible before downstream demand work.
- Circuit currents are user-entered schedule values.
- Group labels are project labels.
- Demand factors are handled separately.
Small board group record
A small board has three grouped load rows that remain below the entered group limit.
- Schedule reference
- CLG-SMALL
- Circuit rows
- 3
- Group limit
- 50 A
- Total row load60 A
- Largest groupLighting at 24 A
Use the status to decide which grouped rows need closer schedule review.
The grouped load record stays below the entered limit and can feed a schedule or phase worksheet.
- Rows use the same current basis.
- The group limit is a user-entered comparison value.
- Phase totals remain a preparation record.
Mixed equipment grouping
A workshop schedule separates tooling and ventilation rows before phase balancing is checked.
- Schedule reference
- CLG-WORKSHOP
- Circuit rows
- 3
- Group limit
- 80 A
- Total row load110 A
- Largest groupWorkshop tools at 80 A
Use the status to decide which grouped rows need closer schedule review.
The grouped result keeps workshop tools separate from mechanical rows for the next schedule step.
- Circuit labels are user-entered.
- No standard demand factors are embedded.
- Switchboard review remains separate.